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NSA US Equity

National Storage Affiliates TrustReal Estate · Real Estate Investment Trusts · CIK 1618563 · FY ends Dec 31
$43.41
+0.00 (+0.00%)
USD · as of 2026-07-22 · marketstack
stale quote — last trade 2026-07-22

NSA · 10-K · period ended 2025-12-31

← all NSA documents
filed 2026-02-26 · EDGAR original ↗

Our rendering of the filing — original pagination and typography are not reproduced, and tables are reduced to their short label cells (the figures live on FA). Nothing is summarized: every line below is the filing's own text.

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nsa-20251231

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

OR

☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number: 001-37351

National Storage Affiliates Trust

(Exact name of Registrant as specified in its charter)

8400 East Prentice Avenue, 9th Floor

Greenwood Village, Colorado80111

(Address of principal executive offices) (Zip code)

(720) 630-2600

(Registrant's telephone number including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading symbols Name of each exchange on which registered

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer ☒ Accelerated Filer ☐

Non-accelerated Filer ☐ Smaller Reporting Company ☐

Emerging Growth Company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to § 240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common shares of beneficial interest of National Storage Affiliates Trust held by non-affiliates of National Storage Affiliates Trust was approximately $2.4 billion as of June 30, 2025. As of February 20, 2026, 77,112,475 common shares of beneficial interest, $0.01 par value per share, were outstanding.

Documents Incorporated by Reference

Portions of the registrant's definitive proxy statement for its annual meeting of shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K.

Auditor Name: KPMG LLP Auditor Location: Denver, Colorado Auditor Firm ID: 185

NATIONAL STORAGE AFFILIATES TRUST

TABLE OF CONTENTS

ANNUAL REPORT ON FORM 10-K

For the Fiscal Year Ended December 31, 2025

Item Page

PART I

1. Business 4

1A. Risk Factors 12

1B. Unresolved Staff Comments 26

1C. Cybersecurity 26

2. Properties 27

3. Legal Proceedings 29

4. Mine Safety Disclosures 29

PART II

6. Selected Financial Data 32

7A. Quantitative and Qualitative Disclosures About Market Risk 50

8. Financial Statements and Supplementary Data 50

9A. Controls and Procedures 51

9B. Other Information 51

PART III

10. Directors, Executive Officers and Corporate Governance 52

11. Executive Compensation 52

13. Certain Relationships and Related Transactions, and Director Independence 52

14. Principal Accounting Fees and Services 52

PART IV

15. Exhibits and Financial Statement Schedules 52

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FORWARD-LOOKING STATEMENTS

National Storage Affiliates Trust and its consolidated subsidiaries (the "Company", "NSA," "we," "our", and "us") make forward-looking statements in this report that are subject to risks and uncertainties. These forward-looking statements include information about possible or assumed future results of our business, financial condition, liquidity, results of operations, plans and objectives. When we use the words "believe," "expect," "anticipate," "estimate," "plan," "continue," "intend," "should," "may," or similar expressions, we intend to identify forward-looking statements.

The forward-looking statements contained in this report reflect our current views about future events and are subject to numerous known and unknown risks, uncertainties, assumptions, and changes in circumstances that may cause our actual results to differ significantly from those expressed in any forward-looking statement.

Statements regarding the following subjects, among others, may be forward-looking:

•market trends in our industry, interest rates, inflation, tariff policies, the debt and lending markets or the general economy;

•our business and investment strategy;

•the acquisition or disposition of properties and other investments, including those under contract, and the ability of our investments to achieve underwritten return expectations and our ability to execute on our investment pipeline;

•the timing of acquisitions or dispositions;

•the integration of the properties managed by our former participating regional operators ("PROs") into the Company, including into our financial and operational reporting infrastructure and internal control framework;

•our operating performance and projected operating results, including our ability to achieve market rents and occupancy levels, reduce operating expenditures and increase the sale of ancillary products and services;

•our ability to access additional off-market acquisitions;

•actions and initiatives of the U.S. federal, state and local government and changes to U.S. federal, state and local government policies, regulations, tax laws and rates (and related accounting guidance), and the execution and impact of these actions, initiatives, policies, regulations and laws;

•the state of the U.S. economy generally or in specific geographic regions, states, territories or municipalities;

•the impact of a shutdown of the U.S. federal government;

•economic trends and economic recoveries, including the level of housing sales that may impact demand;

•our ability to obtain and maintain financing arrangements on favorable terms;

•general volatility of the securities markets in which we participate;

•impacts from major public health events, including unfavorable changes to economic conditions that could adversely affect occupancy levels, rental rates, expenses and the ability of the Company's tenants to pay rent;

•changes in the value of our assets;

•projected capital expenditures;

•the impact of technology and artificial intelligence on our products, operations, and business;

•the implementation of our technology programs and artificial intelligence initiatives (including our ability to effectively implement our integrated Internet marketing strategy or adopt advancements in information technology);

•changes in interest rates, the degree to which our hedging strategies may or may not protect us from interest rate volatility and the impact of such changes on the economy and our industry;

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•our ability to continue to qualify and maintain our qualification as a real estate investment trust for U.S. federal income tax purposes ("REIT");

•availability of qualified personnel;

•the risks of investing through joint ventures, including whether the anticipated benefits from a joint venture are realized or may take longer to realize than expected;

•risks related to or a consequence of natural disasters or acts of violence, major public health events, active shooters, terrorism, insurrection or war that affect the markets in which we operate;

•estimates relating to our ability to make distributions to our shareholders in the future; and

•our understanding of our competition.

The forward-looking statements are based on our beliefs, assumptions and expectations of our future performance, taking into account all information currently available to us. Forward-looking statements are not predictions of future events. These beliefs, assumptions, and expectations can change as a result of many possible events or factors, not all of which are known to us. Readers should carefully review our financial statements and the notes thereto, as well as the sections entitled "Business," "Risk Factors," "Properties," and "Management's Discussion and Analysis of Financial Condition and Results of Operations," described in Item 1, Item 1A, Item 2 and Item 7, respectively, of this Annual Report on Form 10-K and the other documents we file from time to time with the Securities and Exchange Commission. If a change occurs, our business, financial condition, liquidity and results of operations may vary materially from those expressed in our forward-looking statements. Any forward-looking statement speaks only as of the date on which it is made. New risks and uncertainties arise over time, and it is not possible for us to predict those events or how they may affect us. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Except as required by law, we are not obligated to, and do not intend to, update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

PART I

Item 1. Business

General

National Storage Affiliates Trust is a fully integrated, self-administered and self-managed real estate investment trust organized in the state of Maryland on May 16, 2013. We have elected and we believe that we have qualified to be taxed as a REIT for U.S. federal income tax purposes commencing with our taxable year ended December 31, 2015. We serve as the sole general partner of our operating partnership subsidiary, NSA OP, LP (our "operating partnership"), a Delaware limited partnership formed on February 13, 2013 to conduct our business, which is focused on the ownership, operation, and acquisition of self storage properties predominantly located within the top 100 metropolitan statistical areas ("MSAs") throughout the United States. As of December 31, 2025, we held ownership interests in and operated a geographically diversified portfolio of 1,063 self storage properties located in 37 states and Puerto Rico, comprising approximately 69.4 million rentable square feet, configured in approximately 548,000 storage units, excluding three properties classified as held for sale that were sold to a third party in January 2026. We completed our initial public offering in 2015 and our common shares of beneficial interest, $0.01 par value per share ("common shares"), are listed on the New York Stock Exchange under the symbol "NSA."

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Our vice chairperson of the board of trustees and former chairperson of the board of trustees and chief executive officer, Arlen D. Nordhagen, co-founded SecurCare Self Storage, Inc. in 1988 to invest in and manage self storage properties. While growing SecurCare to over 150 self storage properties, Mr. Nordhagen recognized a market opportunity for a differentiated public self storage REIT that would leverage the benefits of national scale by integrating multiple experienced regional self storage operators with local operational focus and expertise, which we refer to as our former PRO structure. Although the PRO structure contributed significantly to our growth over the last decade, the internalization of the PRO structure, which occurred on July 1, 2024, was always a part of our long term vision. Over time, largely through our unconsolidated real estate ventures, retirement of PROs and the internalization of our PRO structure, we have developed a full service internally-staffed property management platform.

We believe that our national platform has significant potential for continued external and internal growth. We seek to further expand our national platform by continuing to pursue strategic acquisitions, as well as to opportunistically partner with institutional funds and other institutional investors in strategic joint venture arrangements while integrating our operations through the implementation of centralized initiatives, including management information systems, revenue enhancement, and cost optimization programs.

Our Property Management Platform

Through our property management platform, we direct, manage and control the day-to-day operations and affairs of our consolidated properties and our unconsolidated real estate ventures. As of December 31, 2025, our property management platform managed and controlled substantially all of our 801 consolidated properties and 262 of our unconsolidated real estate venture properties. The properties are primarily managed by us under the brands of iStorage, Move It, Northwest, RightSpace, SecurCare and Southern.

We earn certain customary fees for managing and operating the properties in the managed unconsolidated real estate ventures and we facilitate tenant insurance and/or tenant warranty protection programs for tenants at these properties in exchange for half of all proceeds from such programs.

Our Consolidated Properties

We seek to own properties that are well located in high quality sub-markets with highly accessible street access and attractive supply and demand characteristics, providing our properties with strong and stable cash flows that we believe are less sensitive to the fluctuations of the general economy. Many of these markets have multiple barriers to entry against increased supply, including zoning restrictions against new construction and new construction costs that we believe are higher than our properties' fair market value. As of December 31, 2025, we owned a geographically diversified portfolio of 801 self storage properties located in 33 states and Puerto Rico, comprising approximately 51.1 million rentable square feet, configured in approximately 403,000 storage units, excluding three properties classified as held for sale that were sold to a third party in January 2026. Of these properties, 289 were acquired by us from our former PROs, 511 were acquired by us from third-party sellers and one was acquired by us from the 2016 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8). A complete listing of, and additional information about, our self storage properties is included in Item 2 of this report.

During the year ended December 31, 2025, we acquired four consolidated self storage properties and annexes to existing properties, all of which were acquired by us from unaffiliated third-party sellers. The following is a summary of our 2025 consolidated acquisition activity (dollars in thousands):

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Number of Number of Rentable

State/Territory Properties Units Square Feet Fair Value

During the year ended December 31, 2025, we sold to unaffiliated third parties 15 self storage properties consisting of approximately 1.0 million rentable square feet configured in approximately 7,000 storage units for approximately $96.9 million.

During the year ended December 31, 2024, we acquired seven consolidated self storage properties and annexes to existing properties, all of which were acquired by us from unaffiliated third-party sellers. The following is a summary of our 2024 consolidated acquisition activity (dollars in thousands):

Number of Number of Rentable

State/Territory Properties Units Square Feet Fair Value

(1) Includes land acquisition with no incremental storage.

(2) Includes annexes to existing properties.

During the year ended December 31, 2024, we sold to unaffiliated third parties 40 self storage properties consisting of approximately 2.6 million rentable square feet configured in approximately 19,000 storage units for approximately $273.1 million and we contributed to the 2024 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8) 56 self storage properties consisting of approximately 3.2 million rentable square feet configured in approximately 24,000 storage units for approximately $343.7 million.

Our Unconsolidated Real Estate Ventures

We seek to opportunistically partner with institutional funds and other institutional investors to acquire attractive portfolios utilizing a promoted return structure. We believe there is significant opportunity for continued external growth by partnering with institutional investors seeking to deploy capital in the self storage industry.

2024 Joint Venture

As of December 31, 2025, our 2024 Joint Venture, in which we have a 25% ownership interest, owned and operated 56 self storage properties containing approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units and located across seven states.

2023 Joint Venture

As of December 31, 2025, our 2023 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, owned and operated 21 self storage properties containing approximately 1.4 million rentable square feet, configured in approximately 9,000 storage units and located across five states.

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2018 Joint Venture

As of December 31, 2025, our 2018 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, owned and operated 104 self storage properties containing approximately 7.9 million rentable square feet, configured in approximately 65,000 storage units and located across 17 states.

2016 Joint Venture

As of December 31, 2025, our 2016 Joint Venture, in which we have a 25% ownership interest, owned and operated 81 properties containing approximately 5.7 million rentable square feet, configured in approximately 47,000 storage units and located across 13 states.

IRE Investment

As of December 31, 2025, we had entered into an agreement with an affiliate of Investment Real Estate Management, LLC (the "IRE Member") to form a new venture to acquire self storage properties (the "IRE Investment"), whereby we committed to provide 75% of the equity capital, up to a maximum of $105.0 million in cash in exchange for preferred equity, and the IRE Member committed to provide 25% of the equity capital, up to a maximum of $35.0 million in cash in exchange for common equity. An affiliate of the IRE Member will serve as the manager of the IRE Investment and will manage the day-to-day operations of the self storage properties. As of December 31, 2025 the IRE Investment did not own any self storage properties.

Our Long-Term Business and Growth Strategies

With our diversified national portfolio of self storage properties, we seek to increase scale, achieve optimal revenue-producing occupancy and rent levels, and increase long-term shareholder value by achieving sustainable long-term growth. Our business and growth strategies to achieve these objectives are as follows:

High Quality Properties in Key Growth Markets. We held ownership interests in and operated a geographically diversified portfolio of 1,063 self storage properties located in 37 states and Puerto Rico, comprising approximately 69.4 million rentable square feet, configured in approximately 548,000 storage units as of December 31, 2025. Over 70% of our consolidated portfolio is located in the top 100 MSAs, based on our 2025 net operating income ("NOI"). We believe that these properties are primarily located in high quality growth markets that have attractive supply and demand characteristics and are less sensitive to the fluctuations of the general economy. Many of these markets have multiple barriers to entry against increased supply, including zoning restrictions against new construction and new construction costs that we believe are higher than our properties' fair market value. Furthermore, we believe that our significant size and the overall geographic diversification of our portfolio reduces risks associated with specific local or regional economic downturns or natural disasters.

Integrated Platform Utilizing Advanced Technology for Enhanced Operational Performance. Our national platform allows us to capture cost savings through integration and centralization, thereby eliminating redundancies and utilizing economies of scale. As compared to a stand-alone operator, our national platform has greater access to lower-cost capital, reduced Internet marketing costs per customer lead, discounted property insurance expense, and reduced overhead costs. In addition, we have sufficient scale for various centralized functions, including financial reporting, the operation of call centers, expanding cell tower leasing, a national credit card processing program, marketing, information technology, legal support, and capital market functions, to achieve substantial cost savings over smaller, individual operators.

Our national platform utilizes advanced technology for our data warehouse program, Internet marketing, our centralized call centers, financial and property analytic dashboards, revenue optimization analytics and expense management tools to enhance operational performance. These centralized programs are positively impacting our business performance, and we believe that they will continue to be a driver of organic growth going forward.

Maximize Property Level Cash Flow. We strive to maximize the cash flows at our properties by leveraging the economies of scale provided by our national platform. We believe that our efficient national platform and centralized infrastructure will enable us to achieve optimal market rents and occupancy, reduce operating expenses and increase the sale by us of ancillary products and services, including tenant insurance, of which we receive a portion of the proceeds, truck rentals and packing supplies.

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Participate in Industry Consolidation Through Acquisitions. The self storage industry is highly fragmented, with the majority of self storage properties in the United States owned by private companies and owners, representing a significant consolidation opportunity. We have established an extensive network of industry relationships and contacts in our respective markets. Through these regional and local connections, we are able to access acquisition opportunities, including some opportunities that are not publicly marketed or sold through auctions. We believe our industry networks and underwriting expertise provide us with a competitive advantage in identifying and selecting attractive acquisition opportunities, in many cases, before they are publicly marketed. We also believe our reputation as a reliable, well-capitalized buyer, along with our willingness to use OP units as transactional currency for a tax-deferred transaction to self storage owners seeking to sell their properties, gives us a competitive advantage over self storage companies that do not have the same transactional history or tax-deferred alternatives.

Strategic Joint Venture Arrangements. We intend to continue to opportunistically partner with institutional funds and other institutional investors to acquire attractive portfolios utilizing a promoted return structure. We believe there is significant opportunity for continued external growth by partnering with institutional investors seeking to deploy capital in the self storage industry. We intend to leverage our property management platform to provide property and asset management services for future strategic joint ventures, generating additional operating profits and third party fee income. In addition, we consider the 75% third-party interest in our managed unconsolidated real estate ventures, which as of December 31, 2025 owned 262 properties, to present a potential acquisition opportunity. This 75% third-party share of gross real estate assets is approximately $2.1 billion based on the historical book value of the joint ventures. Were we to pursue an acquisition of these interests, it could potentially drive our future growth.

Our Financing Strategy

We expect to maintain a flexible approach in financing new property acquisitions. In general, we expect to fund our property acquisitions through a combination of borrowings under bank credit facilities (including term loans and revolving facilities), property-level debt, issuances of OP equity and public and private equity and debt issuances.

Credit Facility. As of December 31, 2025, our unsecured credit facility provided for total borrowings of $1.355 billion (the "credit facility"). The credit facility consists of the following components: (i) a revolving line of credit (the "Revolver") which provided for a total borrowing commitment up to $950.0 million, under which we could borrow, repay and re-borrow amounts, (ii) a $275.0 million tranche D term loan facility (the "Term Loan D") and (iii) a $130.0 million tranche E term loan facility (the "Term Loan E"). As of December 31, 2025, we had the entire amounts drawn on Term Loan D and Term Loan E and we had approximately $400.9 million of outstanding borrowings under the Revolver, and the capacity to borrow an additional $542.1 million under the Revolver while remaining in compliance with the credit facility's financial covenants. As of December 31, 2025, we had an expansion option under the credit facility, which, if exercised in full, would have provided for a total credit facility of $1.900 billion.

Term Loan Facilities, Senior Unsecured Notes and Fixed Rate Mortgages. We will continue to utilize a combination of borrowings, including term loans, senior unsecured notes and fixed rate mortgages, for future acquisitions and to refinance existing debt. As of December 31, 2025, we had $460.0 million of term loan facilities, $1.950 billion of senior unsecured notes and $198.6 million of fixed rate mortgages outstanding.

For additional detail regarding our Credit Facility, Term Loan Facilities and Senior Unsecured Notes, please see Part II, Item 7, "Liquidity and Capital Resources".

Our outstanding term loan facilities and senior unsecured notes are subject to customary affirmative and negative covenants that, among other things, limit the Company's ability to make distributions or certain investments, incur debt, incur liens and enter into certain transactions.

We expect to employ leverage in our capital structure in amounts determined from time to time by our board of trustees. Although our board of trustees has not adopted a policy which limits the total amount of indebtedness that we may incur, it will consider a number of factors in evaluating our level of indebtedness from time to time, as well as the amount of such indebtedness that will be either fixed and variable-rate, and in making financial decisions, including, among others, the following:

•the interest rate of the proposed financing;

•the extent to which the financing impacts our flexibility in managing our properties;

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•prepayment penalties and restrictions on refinancing;

•the purchase price of properties or other assets we acquire with debt financing;

•our long-term objectives with respect to the financing;

•our target investment returns;

•the ability of particular properties, and the Company as a whole, to generate cash flow sufficient to cover expected debt service payments;

•overall level of consolidated indebtedness;

•timing of debt maturities;

•provisions that require recourse and cross-collateralization;

•corporate credit ratios including debt service coverage, debt to total market capitalization and debt to undepreciated assets; and

•the overall ratio of fixed- and variable-rate debt.

Our indebtedness may be recourse, non-recourse or cross-collateralized. If the indebtedness is non-recourse, the collateral will be limited to the particular properties to which the indebtedness relates. In addition, we may invest in properties subject to existing loans secured by mortgages or similar liens, or may refinance properties acquired on a leveraged basis. We may use the proceeds from any borrowings to refinance existing indebtedness, to refinance investments, including the redevelopment of existing properties, for general working capital or for other purposes when we believe it is advisable.

Equity. We may issue common shares or preferred shares in public offerings or private placements, or OP units in our Operating Partnership in connection with property acquisitions. On November 19, 2024, we entered into a new At the Market ("ATM") program authorizing, but not obligating, the sale of up to $400.0 million of common shares from time to time. The timing and amount of these offerings, if any, will be determined by our management based on their evaluation of market conditions, share price, legal requirements and other factors. During the year ended December 31, 2025, we did not sell any common shares through the ATM program.

Joint Ventures. As of December 31, 2025, we owned 262 of our stores through unconsolidated real estate ventures with third parties. Our unconsolidated real estate venture partners typically provide most of the equity capital required for the acquisition of stores owned in these joint ventures. Most joint venture agreements include buy-sell rights, as well as rights of first offer in connection with the sale of stores by the joint venture. We manage the day-to-day operations of the stores owned in our managed joint ventures and participate in major decisions relating to the joint ventures, including the sales of stores or financings by the applicable joint venture.

Sale of Properties. We have not historically sold a high volume of stores. However, we may sell more stores or interests in stores in the future when we conclude we are holding a non-strategic real estate asset or in response to changing economic, financial or investment conditions. For the year ended December 31, 2025, we sold 15 self storage properties to unaffiliated third parties for net proceeds of $96.9 million. For the year ended December 31, 2024, we sold 40 self storage properties to unaffiliated third parties for net proceeds of $273.1 million and contributed 56 self storage properties to the 2024 Joint Venture for net cash proceeds of $343.7 million.

Dividend Reinvestment Plan

In the future, we may adopt a dividend reinvestment plan that will permit shareholders who elect to participate in the plan to have their cash dividends reinvested in additional common shares.

Regulation

General

Generally, self storage properties are subject to various laws, ordinances and regulations, including those relating to lien sale rights and procedures, public accommodations, insurance, privacy and the environment. Changes in any of these laws, ordinances or regulations could increase the potential liability existing or created by tenants or others on our properties. Laws, ordinances, or regulations affecting development, construction, operation, upkeep, safety and taxation requirements may result in significant unanticipated expenditures, loss of self storage sites or other impairments to operations, which would adversely affect our cash flows from operating activities.

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Under the Americans with Disabilities Act of 1990 (the "ADA"), all places of public accommodation are required to meet certain federal requirements related to access and use by disabled persons. A number of additional U.S. federal, state and local laws may also require modifications to our properties, or restrict certain further renovations of the properties, with respect to access thereto by disabled persons. The ADA or these other laws may also apply to our website. For additional information on the ADA, see "Item 1A. Risk Factors—Risks Related to Our Business—Costs associated with complying with the ADA may result in unanticipated expenses."

Insurance activities are subject to state insurance laws and regulations as determined by the particular insurance commissioner for each state in accordance with the McCarran-Ferguson Act, as well as subject to the Gramm-Leach-Bliley Act and the privacy regulations promulgated by the Federal Trade Commission pursuant thereto.

Under various U.S. federal, state and local laws, ordinances and regulations, owners and operators of real estate may be liable for the costs of investigating and remediating certain hazardous substances or other regulated materials on or in such property. The Comprehensive Environmental Response Compensation and Liability Act of 1980, as amended ("CERCLA") and comparable state laws typically impose strict joint and several liabilities without regard to legality of conduct or whether the past or present owner or operator knew of, or was responsible for, the presence of such substances or materials. The presence of such substances or materials, or the failure to properly remediate such substances, may adversely affect the property owner's or operator's ability to lease, sell or rent such property or to borrow using such property as collateral. Persons who transport, dispose, or arrange for the transport, disposal or treatment of hazardous substances or other regulated materials may be liable for the costs of removal or remediation of such substances at a disposal or treatment facility, whether or not such facility is owned or operated by such person. Certain environmental laws impose liability for release of asbestos-containing materials into the air and third-parties may seek recovery from owners or operators of real properties for personal injury (including exposure) associated with asbestos-containing materials. Moreover, the past or present owner or operator of a property from which a release emanates could be liable for any personal injuries or property damages that may result from such releases, as well as any damages to natural resources that may arise from such releases. Additionally, certain environmental laws impose compliance obligations on owners and operators of real property with respect to the management of hazardous materials and other regulated substances onsite. For example, environmental laws govern the management of asbestos-containing materials and lead-based paint. Failure to comply with these laws can result in penalties or other sanctions. In connection with the ownership, operation and management of our current or past properties and any properties that we may acquire and/or manage in the future, we could be legally responsible for environmental, health or safety liabilities or costs, including those relating to a release of hazardous substances or other regulated materials at or emanating from such property. In order to assess the potential for such liability, we conduct an environmental, health and safety assessment of each property prior to acquisition and manage our properties in accordance with environmental laws while we own or operate them. We have engaged qualified, reputable and adequately insured environmental consulting firms to perform environmental site assessments of all of our properties prior to acquisition and are not aware of any environmental issues that are expected to materially impact the operations of any property. For additional information on environmental matters and regulation, see "Item 1A. Risk Factors—Risks Related to Our Business—Environmental compliance costs and liabilities associated with operating our properties may affect our results of operations."

Property management activities are often subject to state real estate brokerage laws and regulations as determined by the particular real estate commission for each state. We may be required to comply with various state privacy and other statutes in connection with the operation of our business. In addition, we may be required to comply with federal, state and local laws, rules and regulations in connection with our communications with our tenants or prospective tenants, including with respect to available units, reservations, payments due, and other matters.

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REIT Qualification

We have elected and we believe that we have qualified to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, (the "Code"), commencing with our taxable year ended on December 31, 2015. We generally will not be subject to U.S. federal income tax on our net taxable income to the extent that we distribute annually all of our net taxable income to our shareholders and maintain our qualification as a REIT. We believe that we have been organized and have operated in conformity with the requirements for qualification and taxation as a REIT under the Code, and we expect that our intended manner of operation will enable us to continue to meet the requirements for qualification and taxation as a REIT. To qualify, and maintain our qualification, as a REIT, we must meet on a continuing basis, through our organization and actual investment and operating results, various requirements under the Code relating to, among other things, the sources of our gross income, the composition and values of our assets, our distribution levels and the diversity of ownership of our shares. If we fail to qualify as a REIT in any taxable year and do not qualify for certain statutory relief provisions, we will be subject to U.S. federal income tax at regular corporate rates and may be precluded from qualifying as a REIT for the subsequent four taxable years following the year during which we failed to qualify as a REIT. Even if we qualify for taxation as a REIT, we still may be subject to some U.S. federal, state and local taxes on our income or assets. In addition, subject to maintaining our qualification as a REIT, a portion of our business is conducted through, and a portion of our income is earned by, one or more taxable REIT subsidiaries ("TRSs"), which are subject to U.S. federal corporate income tax at regular rates. Distributions paid by us generally will not be eligible for taxation at the preferential U.S. federal income tax rates that currently apply to certain distributions received by individuals from taxable corporations, unless such distributions are attributable to dividends received by us from a TRS.

Competition

We compete with many other entities engaged in real estate investment activities for customers and acquisitions of self storage properties and other assets, including national, regional, and local owners, operators, and developers of self storage properties. We compete based on a number of factors including location, rental rates, security, suitability of the property's design to prospective tenants' needs, and the manner in which the property is operated and marketed. We believe that the primary competition for potential customers comes from other self storage properties within a three to five mile radius. We have positioned our properties within their respective markets as high-quality operations that emphasize tenant convenience, security, and professionalism.

We also may compete with numerous other potential buyers when pursuing a possible property for acquisition, which can increase the potential cost of a project. These competing bidders also may possess greater resources, or have a lower cost of capital, than us and therefore be in a better position to acquire a property. However, our use of OP units as transactional currency allows us to structure our acquisitions in tax-deferred transactions. As a result, potential targets who are tax-sensitive might favor us as a suitor.

Our primary competitors in many of our markets for both tenants and acquisition opportunities include local, regional, and national operators, institutional investors, private equity funds, as well as the other public self storage REITs, including Public Storage, CubeSmart, and Extra Space Storage Inc. These entities also seek financing through similar channels to the Company. Therefore, we will continue to compete with these entities for financing opportunities as well as prospective joint venture relationships.

Human Capital

We seek to foster a diverse and inclusive work environment that values each individual team member's talents and contributions, while channeling those efforts toward our common core values of integrity, accountability, humility and compassion. Our success relies on the general professionalism of our employees which are contributing factors to a site's ability to successfully secure rentals, retain tenants and maintain clean and secure self storage properties. We seek to increase employee retention and well-being and our team members enjoy a robust benefit package that includes medical, dental, vision, life insurance, 401K with matching employer contribution and, for our corporate employees, a performance-based bonus incentive plan. As of December 31, 2025, we had 1,458 employees, which includes employees of our property management platform.

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Available Information

We file registration statements, proxy statements, our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and all amendments to those statements and reports with the Securities and Exchange Commission (the "SEC"). Investors may obtain copies of these statements and reports by accessing the SEC's website at www.sec.gov. Our statements and reports and any amendments to any of those statements and reports that we file with the Securities and Exchange Commission are available free of charge as soon as reasonably practicable on our website at www.nsastorage.com. The information contained on our website is not incorporated into this Annual Report on Form 10-K. Our common shares are listed on the New York Stock Exchange under the symbol "NSA."

Item 1A. Risk Factors

An investment in our common shares involves a high degree of risk. Before making an investment decision, you should carefully consider the following risk factors, together with the other information contained in this Annual Report on Form 10-K. If any of the risks discussed in this Annual Report on Form 10-K occurs, our business, financial condition, liquidity and results of operations could be materially and adversely affected.

Risks Related to our Business

Adverse economic or other conditions in the markets in which we do business and more broadly associated with the real estate industry could negatively affect our occupancy levels and rental rates and therefore our operating results and the value of our self storage properties.

Our operating results are dependent upon our ability to achieve optimal occupancy levels and rental rates at our self storage properties. Adverse economic or other conditions in the markets in which we do business, particularly in our markets in Texas, California, Florida, Oregon, and Georgia, which accounted for approximately 19%, 14%, 11%, 9%, and 5%, respectively, of our total rental and other property-related revenues for the year ended December 31, 2025, may lower our occupancy levels and limit our ability to maintain or increase rents or require us to offer rental discounts. Additionally, significantly lower logistics costs could introduce new competitors, such as valet-style storage services, which may reduce the demand for traditional self storage. Customer preferences and/or needs for self storage could change, decline, or shift to other product types, thereby impacting our business model and ability to grow and/or generate revenues. No single customer represented a significant concentration of our 2025 revenues. However, our property portfolio consists solely of self storage properties and is therefore subject to risks inherent in investments in a single industry. The following adverse developments, among others, in the markets in which we do business may adversely affect the operating performance of our properties or our financial results:

•business layoffs or downsizing, industry slowdowns, relocation of businesses and changing demographics;

•periods of economic slowdown, recession, high interest rates, or inflationary environments, declining demand for self storage generally or in a particular area, decreases in the volume of housing market transactions or the public perception that any of these events may occur;

•local or regional real estate market conditions, such as competing properties or products, the oversupply of self storage, or vacancies or changes in self storage space market rents;

•perceptions by prospective tenants of the safety, convenience and attractiveness of our properties and the neighborhoods in which they are located;

•regulatory requirements that increase our operating expenses or limit or prohibit our ability to increase rents;

•actions and initiatives of the U.S. federal, state and local government and changes to U.S. federal, state and local government policies (including tariff policy), regulations, tax laws and rates (and related accounting guidance), and the execution and impact of these actions, initiatives, policies, regulations and laws; and

•other events affecting or shifting consumer discretionary spending.

Any of the above events may reduce our rental revenues, impair our operating results, reduce our ability to satisfy our debt service obligations and make cash distributions to our shareholders and negatively impact our share price, and the effect of the foregoing may be greater than it would be were our investments not limited to a single industry.

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We may not be successful in identifying and consummating suitable acquisitions or integrating and operating such acquisitions, including integrating them into our financial and operational reporting infrastructure and internal control framework in a timely manner, which may impede our growth.

Our ability to expand through acquisitions is integral to our business strategy and requires us to identify suitable acquisition candidates or investment opportunities that meet our criteria and are compatible with our growth strategy. We may not be successful in identifying suitable properties or other assets that meet our acquisition criteria or in consummating acquisitions on satisfactory terms or at all. Failure to identify or consummate acquisitions will slow our growth, which could in turn adversely affect our share price.

Our ability to acquire properties on favorable terms and successfully integrate and operate them, including integrating them into our financial and operational reporting infrastructure in a timely manner, may be constrained by the following significant risks:

•we face competition from national, regional and local owners, operators and developers of self storage properties, which may result in higher property acquisition prices and reduced yields;

•we may not be able to achieve satisfactory completion of due diligence investigations and other customary closing conditions;

•we may fail to finance an acquisition on favorable terms or at all;

•we may spend more time and incur more costs than budgeted to make necessary improvements or renovations to, and to integrate and operate, acquired properties; and

•we may acquire properties subject to liabilities without any recourse, or with only limited recourse, with respect to unknown liabilities such as liabilities for clean-up of environmental contamination, tax liabilities, claims by persons dealing with the former owners or operators of the properties and claims for indemnification by general partners, trustees, officers and others indemnified by the former owners or operators of the properties.

The contributors of properties may make limited representations and warranties to us about the properties and may agree to indemnify us up to a specified amount for a certain period of time following the closing for breaches of those representations and warranties. However, any resulting liabilities identified may not fall within the scope or time frame covered by the indemnification, and we may be required to bear those liabilities, which may materially and adversely affect our operating results, financial condition and business.

We face competition for tenants.

We compete with many other entities engaged in real estate investment activities for tenants, including national, regional and local owners, operators and developers of self storage properties. Actions by our competitors may decrease or prevent increases in the occupancy and rental rates, while increasing the operating expenses, of our properties.

Increases in taxes and regulatory compliance costs, including as a result of changes in law or property reassessments, may reduce our income and adversely impact our cash flows.

Increases in income or other taxes generally are not passed through to tenants under leases and may reduce or negatively impact our net income, funds from operations ("FFO"), core FFO, cash flows, financial condition, ability to pay or refinance our debt obligations, ability to make cash distributions to shareholders, and the trading price of our securities. In addition, the value of our properties may be reassessed for property tax purposes by taxing authorities including as a result of our acquisition activities. For example, our property taxes could increase due to changes in tax rates or removal of limitations on the amount by which our property taxes or property reassessments may increase. From time to time, proposals have been made to remove certain limits on annual real estate tax increases of assessed value of real property in California, where we currently have 86 consolidated properties and 13 unconsolidated properties. While no such initiative has yet been successful, to the extent a similar future initiative is successful, our property tax expense could increase substantially, which could adversely impact our operating results, cash flow, and our ability to pay any expected dividends to our shareholders.

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Similarly, in response to facing severe budgetary problems, many states and jurisdictions are considering or implementing changes in laws such as increasing sales taxes or other types of taxes, increasing the potential liability for environmental, health or safety conditions existing on properties, increasing the restrictions on discharges or other conditions, or mandating paid family leave for employees, which may result in significant unanticipated expenditures, which could result in similar adverse effects.

Legal disputes, settlement and defense costs could have an adverse effect on our operating results.

From time to time we have to make monetary or other settlements or defend actions (including class actions) to resolve tenant, employment-related or other claims and disputes. Settling any such liabilities could negatively impact our operating results and cash available for distribution to shareholders and could also adversely affect our ability to sell, lease, operate or encumber affected properties.

Our storage leases are relatively short-term in nature, which exposes us to the risk that we may have to re-lease our units and we may be unable to do so on attractive terms, on a timely basis or at all.

Our storage leases are relatively short-term in nature, typically month-to-month, which exposes us to the risk that we may have to re-lease our units frequently and we may be unable to do so on attractive terms, on a timely basis or at all. Because these leases generally permit the tenant to leave at the end of the month without penalty, our revenues and operating results may be impacted by declines in market rental rates more quickly than if our leases were for longer terms. In addition, any delay in re-leasing units as vacancies arise would reduce our revenues and harm our operating results.

Security breaches through cyber-attacks, cyber-intrusions, or other methods could disrupt our information technology networks and related systems.

We are increasingly dependent upon automated information technology processes and Internet commerce, and many of our tenants come from the telephone or over the Internet. Moreover, the nature of our business involves the receipt and retention of certain personal information about such tenants, including personally identifiable information of our prospective and current customers and our employees. We centrally manage significant components of our operations with our computer systems, including our financial information and in many cases, we also rely significantly on third-party vendors to retain data, process transactions and provide other systems services. Our networks and operations could be disrupted, and sensitive data could be compromised, by physical or electronic security breaches, targeted against us, our vendors or other organizations, including financial markets or institutions, including by way of or through cyber-attacks or cyber-intrusions over the Internet, malware, ransomware, computer viruses, attachments to e-mails, phishing, employee theft or misuse, or inadequate security controls. Such incidents could also result in significant costs to repair or replace such networks or information systems or to comply with notification obligations, as well as actual monetary losses in case of a cybersecurity incident that resulted in fraudulent payments or other cash transactions. Our operations could be severely impacted by a natural disaster, terrorist attack, attack by hackers, acts of vandalism, data theft, misplaced or lost data, programming or human error, or other circumstances that result in a significant outage of our systems or those of our third party providers, despite our use of back up and redundancy measures. While we may be entitled to damages if our third-party providers fail to satisfy their security-related obligations to us, any award may be insufficient to cover our damages, or we may be unable to recover such award. Although we make efforts to protect the security and integrity of our networks and systems, there can be no assurance that these efforts and measures will be effective or that attempted security breaches or disruptions would not be successful, as such attacks and breaches may be difficult to detect (or not detected at all) and are becoming more sophisticated. In such event, we may experience business interruptions; data loss, ransom, misappropriation, or corruption; theft or misuse of confidential or proprietary information; or litigation and investigation by tenants, governmental or regulatory agencies, or other third parties, which could result in the payment of fines, penalties and other damages. Such events could also have other adverse impacts on us, including breaches of debt covenants, other contractual or REIT compliance obligations, or late or misstated financial reports, and significant diversion of management attention and resources. As a result, such events could have a material adverse effect on our financial condition, results of operations and cash flows and harm our business reputation.

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Our use of or failure to adopt advancements in information technology may hinder or prevent us from achieving strategic objectives or otherwise harm our business.

Our use of or inability to adopt and deliver new technological capabilities and enhancements in line with strategic objectives, including artificial intelligence and machine learning, may put us at a competitive disadvantage; cause us to miss opportunities to innovate, achieve efficiencies, or improve the customer experience; or adversely impact our business, reputation, results of operations, and financial condition. Legislative activity in the privacy area may also result in new laws that are applicable to us and that may hinder our business, including by restricting our use of customer data or otherwise regulating the use of algorithms and automated processing in ways that could materially affect our ability to generate revenues or lead to significant increases in the cost of compliance. In addition, the use of emerging technologies entails risks including risks relating to the possibility of intellectual property infringement or misappropriation; data privacy; new or enhanced governmental or regulatory scrutiny, requirements, litigation, or other liability; ethical concerns; negative consumer perceptions as to automation and artificial intelligence; or other complications or liabilities that could adversely affect our business, reputation, results of operations, or financial results.

Our use of artificial intelligence could expose us to various risks.

We have begun to utilize artificial intelligence technologies in various aspects of our business. Artificial intelligence technologies are susceptible to errors and other malfunctions which could lead to operational challenges and reputational risks. In addition, we may be subject to increasing regulations related to our use of these technologies, including regulations related to privacy, data security, and intellectual property rights, which could expose us to legal risks.

Costs associated with complying with the ADA may result in unanticipated expenses.

Under the ADA and other federal, state and local laws, we are required to meet certain requirements related to access and use by disabled persons. Noncompliance with the ADA could result in the imposition of fines or an award of damages to private litigants and also could result in an order to correct any non-complying feature, which could result in substantial capital expenditures. If one or more of our properties or websites is not in compliance with the ADA or similar laws, then we would be required to incur additional costs to bring the property or websites into compliance. If we incur such costs and they are substantial, our financial condition, results of operations, cash flow, per share trading price of our common shares and our ability to satisfy our debt service obligations and to make cash distributions to our shareholders could be adversely affected.

Environmental compliance costs and liabilities associated with operating our properties may affect our results of operations.

Under certain U.S. federal, state and local environmental laws, ordinances and regulations, past or present owners and operators of real estate may be liable for, among other things, the costs of investigating and remediating certain hazardous substances or other regulated materials on or in such property. No assurances can be given that existing environmental assessments or studies with respect to any of our properties reveal all environmental, health or safety liabilities, that any prior owner or operator of our properties did not create any material environmental, health or safety condition not known to us, or that a material environmental, health or safety condition does not otherwise exist as to any one or more of our properties. There also exists the risk that material environmental, health or safety conditions, liabilities or compliance concerns may have arisen after the review was completed or may arise in the future. Finally, future laws, ordinances or regulations and future interpretations of existing laws, ordinances or regulations may impose additional material environmental, health or safety liability.

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We have tenant insurance- and/or tenant protection plan-related arrangements that are in some cases subject to state-specific governmental regulation, which may adversely affect our results.

We have tenant insurance- and/or tenant protection plan-related arrangements with regulated insurance companies and our tenants. The tenant insurance and tenant protection plan businesses, including the payments associated with these arrangements, are in some cases subject to state-specific governmental regulation. State regulatory authorities generally have broad discretion to grant, renew and revoke licenses and approvals, to promulgate, interpret and implement regulations, and to evaluate compliance with regulations through periodic examinations, audits and investigations of the affairs of insurance industry participants. As a result of such action, we may be temporarily or permanently suspended from continuing some or all of our tenant insurance- and/or tenant protection plan-related activities, or otherwise fined or penalized or suffer an adverse judgment, which could adversely affect our business and results of operations.

Privacy concerns could result in regulatory changes that may harm our business.

Personal privacy has become a significant issue in the jurisdictions in which we operate. Many jurisdictions in which we operate have imposed or in the future may impose restrictions and requirements on the use of personal information by those collecting such information. For example, U.S. state laws such as the California Consumer Privacy Act provide consumers with expansive rights and control over personal information obtained by or shared with certain covered businesses. Changes to law or regulations or the passage of new laws affecting privacy, if applicable to our business, could impose additional costs and liability on us and could limit our use and disclosure of such information.

We face possible risks and costs associated with the effects of climate change and severe weather, as well as the transition to a low-carbon economy and other steps taken to prevent or mitigate climate change.

We cannot predict the rate at which climate change will progress. However, the physical effects of climate change could have a material adverse effect on our properties, operations, and business. To the extent that climate change impacts changes in weather patterns, our markets could experience severe weather, including hurricanes, tornados, earthquakes, severe winter storms, wildfires and coastal flooding due to increases in storm intensity and rising sea levels. Over time, these conditions could result in physical damage to, or declining demand, for storage at our properties or in our inability to operate them at all. Climate change and severe weather may also have indirect effects on our business by increasing the cost of, or decreasing the availability of, property insurance, utilities or other important vendor services on terms we find acceptable, by increasing the costs of energy, maintenance, repair of fire, water and/or wind damage, and snow removal at our properties. There can be no assurance that climate change and severe weather, or the potential impacts of these events on our vendors, will not have a material adverse effect on our properties, operations, or business.

Changes in federal, state, and local legislation and regulation as well as international pacts or treaties based on concerns about climate change could result in increased capital expenditures on our existing properties (for example, to improve their energy efficiency and/or resistance to severe weather) without a corresponding increase in revenue, which may result in adverse impacts to our net income. In recent years, there have been, and in the future there may be, a number of new legal efforts to reduce greenhouse gas emissions and to take other similar actions to combat the effects of climate change, including at the international level and at the U.S. federal, state and local levels. Potential social pressure related to climate change and actions to mitigate climate change could also in the future result in consumers reducing their individual carbon footprints by owning fewer durable material consumer goods, collectibles, and other such items requiring storage, resulting in a reduced demand for our self storage space. In addition, our reputation and investor relationships could be damaged as a result of our involvement with activities perceived to be causing or exacerbating climate change, as well as any decisions we make to continue to conduct or change our activities in response to considerations relating to climate change.

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International trade disputes, including U.S. trade tariffs and retaliatory tariffs, could adversely impact our business.

International trade disputes, including threatened or implemented tariffs imposed by the U.S. and threatened or implemented tariffs imposed by foreign countries in retaliation, could result in inflationary pressures that directly impact our costs, such as costs for steel, lumber and other materials applicable to our expansions and redevelopment projects. Trade disputes could also adversely impact global supply chains which could further increase costs for us or delay delivery of key inventories and supplies. Tariffs and trade restrictions can be announced with little or no advance notice, and we may not be able to effectively mitigate all adverse impacts from such measures. If we are not able to navigate these changes, it could have a material adverse effect on our business.

Uninsured losses or losses in excess of our insurance coverage could adversely affect our financial condition, operating results and cash flow.

We maintain comprehensive liability, fire, flood, earthquake and wind (as deemed necessary or as required by our lenders), extended coverage and rental loss insurance with respect to our properties. Certain types of losses, however, may be either uninsurable or not economically insurable either in total or in part (due to location or otherwise), such as losses due to earthquakes, hurricanes, tornadoes, floods, riots, acts of war or terrorism. Should an uninsured loss occur, we could lose both our investment in and anticipated profits and cash flow from a property or otherwise be subject to significant liabilities. In addition, if any such loss is insured, we may be required to pay significant amounts on any claim for recovery of such a loss prior to our insurer being obligated to reimburse us for the loss, or the amount of the loss may exceed our coverage for the loss. We currently self-insure a portion of our commercial insurance deductible risk through our captive insurance company. To the extent that our captive insurance company is unable to bear that risk, we may be required to fund additional capital to our captive insurance company or we may be required to bear that loss. As a result, our operating results may be adversely affected.

Illiquidity of real estate investments could significantly impede our ability to respond to adverse changes in the performance of our properties.

Because real estate investments are relatively illiquid and we have agreed and may in the future agree to certain transfer restrictions with respect to our properties, our ability to promptly sell one or more properties in our portfolio in response to changing economic, financial and investment conditions is limited. The real estate market is affected by many factors, such as general economic conditions, availability of financing, interest rates, supply and demand, and others, that are beyond our control. We cannot predict whether we will be able to sell any property for the price or on the terms set by us or whether any price or other terms offered by a prospective purchaser would be acceptable to us. We also cannot predict the length of time needed to find a willing purchaser and to close the sale of a property. In addition, we may be required to expend funds to correct defects or to make improvements before a property can be sold. We cannot assure you that we will have funds available to correct those defects or to make those improvements.

Our business could be harmed if key personnel terminate their employment with us.

Our success depends, to a significant extent, on the continued services of Arlen D. Nordhagen, Tamara D. Fischer, David G. Cramer, Brandon S. Togashi, William S. Cowan and Tiffany S. Kenyon and the other members of our senior management team. We have entered into employment agreements with Mr. Nordhagen, Ms. Fischer, Mr. Cramer, Mr. Togashi, Mr. Cowan and Ms. Kenyon, which provide for an initial term of employment and automatic one-year extensions thereafter unless either party provides at least 90 days' notice of non-renewal. Notwithstanding these agreements, there can be no assurance that any of them will remain employed by us. The loss of services of one or more members of our senior management team could harm our business and our prospects. This risk may be heightened during periods of tight labor market conditions.

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We invest in strategic joint ventures that subject us to additional risks.

Some of our investments are, and in the future may be, structured as strategic joint ventures. Part of our strategy is to opportunistically partner with institutional funds and other institutional investors or third parties to acquire attractive portfolios which may be through a promoted return structure. These arrangements may be driven by the magnitude of capital required to complete the acquisitions and maintain the acquired portfolios or other considerations. Such arrangements involve risks not present where a third party is not involved, including the possibility that partners or co-venturers might become bankrupt or otherwise fail to fund their share of required capital contributions. Additionally, partners or co-venturers might at any time have economic or other business interests or goals different from us and or in competition with us.

Joint ventures generally provide for a reduced level of control over an acquired project because governance rights are shared with others. Accordingly, certain major decisions relating to joint ventures, including decisions relating to, among other things, the approval of annual budgets, sales and acquisitions of properties, financings, and certain actions relating to bankruptcy, are often made by a majority vote of the investors or by separate agreements. In addition, such decisions may be subject to the risk that the partners or co-venturers may make certain decisions with which we do not agree or otherwise act in a manner that does not serve our best interests. Because we may not have the ability to exercise control over such operations, we may not be able to realize some or all of the benefits that we believe will be created from our involvement. At times, we and our partners or co-venturers may also each have the right to trigger a buy-sell arrangement, which could cause us to sell our interest, or acquire our partners' or co-venturers' interest, at a time when we otherwise would not have initiated such a transaction. If any of the foregoing were to occur, our business, financial condition and results of operations could suffer as a result.

Natural disasters, public health emergencies and other crises, or consumer protection could adversely impact or cause significant disruption to our financial condition, results of operations and cash flows.

The impact of natural disasters, public health emergencies and other crises, and any government responses to such emergencies, or regulations passed in an attempt to protect consumers could among other things, affect our tenants' ability to meet their obligations to us, impact consumer discretionary spending, lower demand for storage facilities, lead to lower rental rates, inability to raise rents, reduced late fee collection, compel complete or partial closures and operational changes at our properties, reduce demand for growth opportunities, such as acquiring new properties, and interrupt the availability of our personnel. Although the self storage industry has historically been resilient to ordinary market downturns, the impact of natural disasters, public health emergencies and related regulations including those that limit our ability to raise rents could materially and adversely affect our financial condition, results of operations and cash flows and will largely depend on future developments, which are highly uncertain and cannot be predicted.

Terrorist attacks, active shooter incidents and other acts of violence or war may adversely impact our performance and may affect the markets on which our securities are traded.

Terrorist attacks at or against our stores, our interests, the United States or abroad, may negatively impact our operations and the value of our securities. Attacks, armed conflicts or active-shooter situations could negatively impact the demand for self storage and increase the cost of insurance coverage for our stores, which could reduce our profitability and cash flow. Furthermore, any terrorist attacks, armed conflicts or active-shooter situations could result in increased volatility in or damage to the United States and worldwide financial markets and economy.

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Risks Related to Our Structure

Conflicts of interest could arise with respect to certain transactions between the holders of OP units, on the one hand, and us and our shareholders, on the other.

Conflicts of interest could arise with respect to the interests of holders of OP units, on the one hand, which include members of our senior management team and trustees, and us and our shareholders, on the other hand. Certain business combinations, the sale, disposition or transfer of certain of our assets or the repayment of certain indebtedness that may be desirable to us and our shareholders could have adverse tax consequences to such unit holders. In addition, under Maryland law, our trustees and officers have duties to the Company in connection with their management of the Company, however, under Delaware law, as a general partner, we have fiduciary duties to our operating partnership and to the limited partners in connection with the management of our operating partnership. Our duties as a general partner may come into conflict with the duties of our trustees and officers to the Company and our shareholders and we are not required to resolve such conflicts in favor of either the Company or the limited partners in our operating partnership. Further, there can be no assurance that any procedural protections we implement to address these or other conflicts of interest will result in optimal outcomes for us and our shareholders.

The partnership agreement of our operating partnership contains provisions that may delay, defer or prevent a change in control.

The partnership agreement of our operating partnership provides that in the case of certain change of control transactions in which we have not received the consent of OP unit holders holding more than 50% of the OP units (other than those held by us or our subsidiaries), such transaction is required to be approved by a company-wide vote of limited partners holding more than 50% of our outstanding OP units in which OP units (including for this purpose OP units held by us and our subsidiaries) are voted and in which we will be deemed to vote the OP units held by us and our subsidiaries in proportion to the manner in which all of our outstanding common shares were voted at a shareholders meeting relating to such transaction. These approval rights could delay, deter, or prevent a transaction or a change in control that might involve a premium price for our common shares or otherwise be in the best interests of our shareholders.

Certain provisions of the Maryland General Corporation Law (the "MGCL") and of our bylaws and our declaration of trust could inhibit a change in our control and have an adverse impact on the price of our shares.

The MGCL, our bylaws and our declaration of trust contain provisions that may discourage, delay or make more difficult a change in our control. We are subject to the Maryland Business Combination Act (the "MBCA"). Our board has adopted a resolution exempting from the MBCA any business combinations between us and (1) any other person, provided that the business combination is first approved by our board (including a majority of disinterested trustees), (2) Arlen D. Nordhagen and any of his affiliates and associates and (3) any person acting in concert with the foregoing. As a result, such persons may be able to enter into business combinations with us that may not be in the best interests of our shareholders without compliance by us with the moratorium supermajority vote requirements and other provisions of the statute. If this resolution is repealed or our board does not approve a business combination, the MBCA may discourage third parties from trying to acquire control of us and increase the difficulty of consummating such an offer.

The Maryland Control Share Acquisition Act (the "MCSAA") provides that holders of "control shares" of a Maryland real estate investment trust acquired in a "control share acquisition" have no voting rights with respect to such shares except to the extent approved by our shareholders by the affirmative vote of at least two-thirds of all the votes entitled to be cast on the matter, excluding votes entitled to be cast by the acquirer of control shares, our officers and our trustees who are also our employees. Our bylaws exempt from the MCSAA acquisitions of our shares by any person. If we amend our bylaws to repeal the exemption from MCSAA, the MCSAA also may make it more difficult for a third party to obtain control of us and increase the difficulty of consummating such an offer.

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We have also adopted other measures that may make it difficult for a third party to obtain control of us, including provisions of our declaration of trust and bylaws limiting the liability of our present and former trustees and officers to us and our shareholders for money damages to the maximum extent permitted under Maryland law, requiring us to indemnify our present and former trustees and officers for actions taken in their official capacities, permitting (subject to the rights of holders of any class or series of preferred shares) removal of a trustee, with or without cause, only by the affirmative vote of at least two-thirds of the votes entitled to be cast generally in the election of trustees, and authorizing our board (without shareholder approval) to classify or reclassify our shares in one or more classes or series, to cause the issuance of additional shares and to amend our declaration of trust to increase or decrease the number of shares that we have authority to issue. These provisions, as well as other provisions of our declaration of trust and bylaws, may delay, defer or prevent a transaction or a change in control that might otherwise be in the best interests of our shareholders.

Restrictions on ownership and transfer of our shares may restrict change of control or business combination opportunities in which our shareholders might receive a premium for their shares.

In order for us to qualify as a REIT for each taxable year, no more than 50% in value of our outstanding shares may be owned, directly or constructively, by five or fewer individuals during the last half of any calendar year, and at least 100 persons must beneficially own our shares during at least 335 days of a taxable year of 12 months, or during a proportionate portion of a shorter taxable year. "Individuals" for this purpose include natural persons, private foundations, some employee benefit plans and trusts, and some charitable trusts. To assist us in preserving our REIT qualification, among other purposes, our declaration of trust generally prohibits, among other limitations, any person from beneficially or constructively owning more than 9.8% in value or in number of shares, whichever is more restrictive, of our aggregate outstanding shares of all classes and series, the outstanding shares of any class or series of our preferred shares or our outstanding common shares. These ownership limits and the other restrictions on ownership and transfer of our shares contained in our declaration of trust could have the effect of discouraging a takeover or other transaction in which holders of our common shares might receive a premium for their shares over the then prevailing market price or which holders might believe to be otherwise in their best interests. Our board of trustees has established exemptions from these ownership limits which permits certain of our institutional investors to hold up to 20% of our common shares and up to 25% of our preferred shares.

Risks Related to Our Debt Financings

There are risks associated with our indebtedness.

Our level of debt and the limitations imposed on us by our debt agreements could have significant adverse consequences, including the following:

•our cash flow may be insufficient to meet our required principal and interest payments;

•to satisfy our debt obligations, we may be forced to dispose of one or more of our properties, possibly on disadvantageous terms;

•our debt level could place us at a competitive disadvantage compared to our competitors with less debt; and

•we may violate our restrictive covenants or otherwise default on our obligations, which may entitle our creditors to accelerate our debt obligations, foreclose on our properties securing our debt, enforce our guarantees and/or trigger default on our other indebtedness.

We depend on external sources of capital that are outside of our control, which could adversely affect our ability to acquire or develop properties, satisfy our debt obligations and/or make distributions to shareholders.

We depend on external sources of capital to acquire properties, to satisfy our debt obligations and to make distributions to our shareholders required to maintain our qualification as a REIT, and these sources of capital may not be available on favorable terms, or at all. Our access to external sources of capital depends on a number of factors, including the market's perception of our growth potential and our current and potential future earnings and our ability to continue to qualify as a REIT for U.S. federal income tax purposes. If we are unable to obtain external sources of capital, or if such capital is not available on acceptable terms, we may not be able to acquire properties when strategic opportunities exist, satisfy our debt obligations or make cash distributions to our shareholders that would permit us to qualify as a REIT or avoid paying tax on all of our net taxable income.

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Increases in interest rates may increase our interest expense and adversely affect our cash flow and our ability to service our indebtedness, make cash distributions to our shareholders, and acquire or sell properties and our decision to hedge against interest rate risk might not be effective.

As of December 31, 2025, we had approximately $3.4 billion of debt outstanding, of which approximately $405.9 million, or 11.9%, is subject to variable interest rates (excluding variable-rate debt subject to interest rate swaps). If interest rates increase, our debt service obligations on variable-rate debt will increase even though the amount borrowed remains the same, while our net income, cash flows, and our ability to pay cash distributions to our shareholders correspondingly decrease. In addition, increased interest rates make the financing of any acquisition and investment activity as well as the refinancing of existing debt more costly and could decrease the amount third parties are willing to pay for any properties that we wish to sell.

Although we have historically sought, and may in the future seek, to manage our exposure to interest rate volatility by using interest rate hedging arrangements, these arrangements may not be effective. Developing an effective interest rate risk strategy is complex and no strategy can completely insulate us from risks associated with interest rate fluctuations. Failure to hedge effectively against interest rate changes may adversely affect our financial condition, results of operations and ability to make cash distributions to our shareholders.

The terms and covenants relating to our indebtedness could adversely impact our economic performance.

Our credit facility, term loan facilities and senior unsecured notes contain (and any new or amended facility we may enter into from time to time will likely contain) customary affirmative and negative covenants, including financial covenants that, among other things, cap our total leverage and our unsecured debt. In the event that we fail to satisfy our covenants, we would be in default under our debt agreements and may be required to repay such debt with capital from other sources. Under such circumstances, other sources of debt or equity capital may not be available to us, or may be available only on unattractive terms. Moreover, the presence of such covenants could cause us to operate our business with a view toward compliance with such covenants, which might not produce optimal returns for shareholders.

Risks Related to Our Qualification as a REIT

Our failure to remain qualified as a REIT would subject us to U.S. federal income tax and applicable state and local taxes, which would reduce the amount of operating cash flow to our shareholders.

We have elected and we believe that we have qualified to be taxed as a REIT commencing with our taxable year ended December 31, 2015. We have not requested, and do not intend to request, a ruling from the Internal Revenue Service ("IRS"), that we qualify as a REIT. Qualification as a REIT involves the application of highly technical and complex Code provisions and Treasury Regulations promulgated thereunder for which there are limited judicial and administrative interpretations. To qualify as a REIT, we must meet, on an ongoing basis through actual operating results, various tests regarding the nature and diversification of our assets and our income, the ownership of our outstanding shares and the amount of our distributions. Our ability to satisfy these asset tests depends upon our analysis of the characterization and fair market values of our assets, some of which are not susceptible to a precise determination, and for which we will not obtain independent appraisals. Moreover, new legislation, court decisions or administrative guidance may, in each case possibly with retroactive effect, make it more difficult or impossible for us to qualify as a REIT. Thus, while we believe that we have been organized and operated and we intend to operate so that we will continue to qualify as a REIT, given the highly complex nature of the rules governing REITs, the ongoing importance of factual determinations and the possibility of future changes in our circumstances, no assurance can be given that we have qualified or will so qualify for any particular year. These considerations also might restrict the types of assets that we can acquire or services that we can provide in the future.

We own and may in the future acquire direct or indirect interests in entities that have elected or will elect to be treated as REITs under the Code (each a "Subsidiary REIT"). If a Subsidiary REIT were to fail to qualify as a REIT, then (i) that Subsidiary REIT would become subject to U.S. federal income tax, (ii) shares in such Subsidiary REIT would cease to be qualifying assets for purposes of the asset tests applicable to REITs, and (iii) it is possible that we would fail certain of the tests applicable to REITs, in which event we would fail to qualify as a REIT unless we qualify for certain statutory relief provisions.

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In addition, in order to qualify as a REIT, prior to the end of the taxable year, we must also distribute any earnings and profits of any property we acquire in certain tax-deferred transactions to the extent such earnings accrued at a time when such corporation did not qualify as a REIT. We have entered into certain transactions involving the tax-deferred acquisition of target corporations. We believe that we have distributed any earnings and profits of such target corporations attributable to any period that such corporations did not qualify as a REIT. However, no assurances can be provided in this regard, and if there is a determination that we have inherited and retained any such earnings and profits, our qualification as a REIT could be adversely impacted.

If we fail to qualify as a REIT in any taxable year, and we do not qualify for certain statutory relief provisions, we would be required to pay U.S. federal income tax on our taxable income at regular corporate rates, and distributions to our shareholders would not be deductible by us in determining our taxable income. In such a case, we might need to borrow money, sell assets, or reduce or even cease making distributions in order to pay our taxes. Our payment of income tax would reduce significantly the amount of operating cash flow to our shareholders. Furthermore, if we fail to maintain our qualification as a REIT, we no longer would be required to make distributions to our shareholders. In addition, unless we were eligible for certain statutory relief provisions, we could not re-elect to be taxed as a REIT until the fifth calendar year following the year in which we failed to qualify.

Even if we qualify as a REIT, we may face other tax liabilities that reduce our cash flow.

Even if we qualify for taxation as a REIT, we may be subject to certain U.S. federal, state and local taxes on our income and assets, including taxes on any undistributed income, state or local income and property and transfer taxes, including real property transfer taxes. In addition, we could, in certain circumstances, be required to pay an excise or penalty tax (which could be significant in amount) in order to utilize one or more relief provisions under the Code to maintain our qualification as a REIT. Any of these taxes would decrease operating cash flow to our shareholders.

In order to qualify as a REIT, we must distribute to our shareholders each calendar year at least 90% of our net taxable income (excluding net capital gain). To the extent that we satisfy the 90% distribution requirement, but distribute less than 100% of our net taxable income (including net capital gain), we would be subject to U.S. federal corporate income tax on our undistributed net taxable income. In addition, we will incur a 4% non-deductible excise tax on the amount, if any, by which our distributions in any calendar year are less than a minimum amount specified under U.S. federal income tax laws. Although we intend to distribute our net taxable income to our shareholders in a manner that would avoid this 4% tax, there can be no assurance that we will be able to do so, due to timing differences between our actual receipt of cash and the inclusion of items in our income for U.S. federal income tax purposes, the effect of non-deductible capital expenditures, or the creation of reserves or required debt or amortization payments.

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In addition, we will be subject to a 100% tax on any income from sales or other dispositions of property (other than property treated as foreclosure property under the Code) that is held as inventory or primarily for sale to customers in the ordinary course of a trade or business by a REIT, either directly or indirectly through certain pass-through subsidiaries (a "prohibited transaction"). In order to meet the REIT qualification requirements, or to avoid the imposition of the penalty tax on prohibited transactions, we may hold some of our assets or provide certain services to our tenants through one or more TRSs, which generally will be subject to U.S. federal, state and local corporate taxes. In addition, if a REIT lends money to a TRS, the TRS may be unable to deduct all or a portion of the interest paid to the REIT, which could increase the tax liability of the TRS. In addition, the Code imposes a 100% tax on certain transactions between a TRS and its parent REIT that are not conducted on an arm's length basis. We intend to structure transactions with any TRS on terms that we believe are arm's length to avoid incurring the 100% excise tax described above. There can be no assurances, however, that we will be able to avoid application of the 100% tax. Furthermore, if we acquire appreciated assets from a corporation that is or has been a subchapter C corporation in a transaction in which the adjusted tax basis of such assets in our hands is less than the fair market value of the assets, determined at the time we acquired such assets, and if we subsequently dispose of any such assets during the 5-year period following the acquisition of the assets from the C corporation, we will be subject to tax at the highest corporate tax rates on any gain from the disposition of such assets to the extent of the excess of the fair market value of the assets on the date that we acquired such assets over the basis of such assets on such date, which we refer to as built-in gains. In addition, we have entered into certain transactions in which we acquired target entities in tax-deferred transactions. To the extent such entities had outstanding U.S. federal income tax or other tax liabilities, we would succeed to such liabilities.Payment of these taxes generally could materially and adversely affect our income, cash flow, results of operations, financial condition, liquidity and prospects, and could adversely affect the value of our common shares and our ability to make distributions to our shareholders.

Complying with the REIT requirements may cause us to forgo and/or liquidate otherwise attractive investments, and in some situations, to maintain our REIT qualification, we may be forced to borrow funds during unfavorable market conditions.

To qualify as a REIT, we must ensure that at least 75% of our gross income for each taxable year, excluding certain amounts, is derived from certain real property-related sources, and at least 95% of our gross income for each taxable year, excluding certain amounts, is derived from certain real property-related sources and passive income such as dividends and interest. In addition, we must ensure that, at the end of each calendar quarter, at least 75% of the value of our total assets consists of cash, cash items, U.S. government securities and qualified real estate assets. The remainder of our investment in securities generally cannot include more than 10% of the outstanding voting securities of any one issuer (other than U.S. government securities, securities of corporations that are treated as TRSs and qualified real estate assets) or more than 10% of the total value of the outstanding securities of any one issuer (other than government securities, securities of corporations that are treated as TRSs and qualified real estate assets). In addition, in general, no more than 5% of the value of our assets can consist of the securities of any one issuer (other than U.S. government securities, securities of corporations that are treated as TRSs and qualified real estate assets), no more than 20% (25% for taxable years beginning after December 31, 2025) of the value of our total assets can be represented by securities of one or more TRSs and no more than 25% of the value of our assets can consist of debt instruments issued by publicly offered REITs that are not otherwise secured by real property. If we fail to comply with these asset requirements at the end of any calendar quarter, we must correct the failure within 30 days after the end of the calendar quarter or qualify for certain statutory relief provisions to avoid losing our REIT qualification and suffering adverse tax consequences.

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To meet these tests, we may be required to take or forgo taking actions that we would otherwise consider advantageous. For instance, in order to satisfy the gross income or asset tests applicable to REITs under the Code, we may be required to forgo investments that we otherwise would make, and we may be required to liquidate from our portfolio otherwise attractive investments. In addition, we may be required to make distributions to shareholders at disadvantageous times or when we do not have funds readily available for distribution. As a result, we may need to borrow funds to meet the REIT distribution requirements even if the then prevailing market conditions are not favorable for these borrowings. Our access to third-party sources of capital depends on a number of factors, including the market's perception of our growth potential, our current debt levels, the per share trading price of our common shares, and our current and potential future earnings. We cannot assure you that we will have access to such capital on favorable terms at the desired times, or at all, which may cause us to curtail our investment activities and/or to dispose of assets at inopportune times. These actions could reduce our income and amounts available for distribution to our shareholders. Thus, compliance with the REIT requirements may hinder our investment performance.

If our operating partnership is treated as a corporation for U.S. federal income tax purposes, we will cease to qualify as a REIT.

We believe our operating partnership qualifies as a partnership for U.S. federal income tax purposes, and accordingly generally will not be subject to U.S. federal income tax on its income. Instead, each of its partners, including us, will be required to pay tax on its allocable share of our operating partnership's income. No assurance can be provided, however, that the IRS will not challenge our operating partnership's status as a partnership for U.S. federal income tax purposes, or that a court would not sustain such a challenge. If the IRS were successful in treating our operating partnership as a corporation for U.S. federal income tax purposes, we would fail to meet the gross income tests and certain of the asset tests applicable to REITs, we would cease to qualify as a REIT, and both we and our operating partnership would become subject to U.S. federal, state and local income tax. The payment by our operating partnership of income tax would reduce significantly the amount of cash available to our operating partnership to satisfy obligations to make principal and interest payments on its debt and to make distribution to its partners, including us.

Complying with REIT requirements may limit our ability to hedge effectively and may cause us to incur tax liabilities.

The REIT provisions of the Code may limit our ability to hedge our assets and operations. Under these provisions, any income that we generate from transactions intended to hedge our interest rate risk will be excluded from gross income for purposes of the REIT 75% and 95% gross income tests if (i) the instrument (a) hedges interest rate risk on liabilities used to carry or acquire real estate assets or (b) hedges an instrument described in clause (a) for a period following the extinguishment of the liability or the disposition of the asset that was previously hedged by the hedged instrument, and (ii) the relevant instrument is properly identified under applicable Treasury regulations. Income from hedging transactions that does not meet these requirements will generally constitute non-qualifying income for purposes of both the REIT 75% and 95% gross income tests. As a result of these rules, we may have to limit our use of hedging techniques that might otherwise be advantageous or implement those hedges through a TRS. This could increase the cost of our hedging activities because our TRS would be subject to tax on gains or expose us to greater risks associated with changes in interest rates than we would otherwise want to bear, and we generally would not benefit from losses in our TRS, although, subject to limitation, such losses may be carried forward to offset future taxable income of the TRS.

The ability of our board of trustees to revoke our REIT election without shareholder approval may cause adverse consequences to our shareholders.

Our declaration of trust provides that the board of trustees may revoke or otherwise terminate our REIT election, without the approval of our shareholders, if the board determines that it is no longer in our best interest to attempt to, or continue to, qualify as a REIT. If we cease to qualify as a REIT, we would become subject to U.S. federal income tax on our net taxable income and we generally would no longer be required to distribute any of our net taxable income to our shareholders, which may have adverse consequences on our total return to our shareholders.

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Legislative or regulatory tax changes related to REITs could materially and adversely affect our business.

At any time, the U.S. federal income tax laws or regulations governing REITs or the administrative interpretations of those laws or regulations may be changed, possibly with retroactive effect. We cannot predict if or when any new U.S. federal income tax law, regulation or administrative interpretation, or any amendment to any existing U.S. federal income tax law, regulation or administrative interpretation, will be adopted, promulgated or become effective or whether any such law, regulation or interpretation may take effect retroactively. We and our shareholders could be adversely affected by any such change in, or any new, U.S. federal income tax law, regulation or administrative interpretation. Stockholders are urged to consult with their tax advisors regarding the effects of the other legislative, regulatory or administrative developments on an investment in the Company's common stock.

Risks Related to Our Common Shares and Preferred Shares

Common shares and preferred shares eligible for future sale may have adverse effects on our share price.

Subject to applicable law and the rules of any stock exchange on which our shares may be listed or traded, our board, without common shareholder approval, may authorize us to issue additional authorized and unissued common shares and preferred shares on the terms and for the consideration it deems appropriate and may amend our declaration of trust to increase the total number of shares, or the number of shares of any class or series, that we are authorized to issue. In addition, our operating partnership may issue OP units, which are redeemable for cash or, at our option exchangeable on a one-for-one basis into common shares after an agreed period of time and certain other conditions, preferred units of limited partnership interest, which are redeemable for cash or, at our option exchangeable on a one-for-one basis into our 6.000% Series A cumulative redeemable preferred shares of beneficial interest ("Series A Preferred Shares") or other types of partnership units that may be exchanged for cash or other securities of our Company. We have also granted registration rights to those persons who will be eligible to receive common shares issuable upon exchange of OP units and preferred shares issuable upon exchange of preferred units issued in our contribution transactions.

We cannot predict the effect, if any, of future sales of our common or preferred shares or the availability of shares for future sales, on the market price of our common or preferred shares. The market price of our common shares may decline significantly when the restrictions on resale by certain of our shareholders lapse. Sales of substantial amounts of common or preferred shares or the perception that such sales could occur may adversely affect the prevailing market price for our common shares.

We cannot assure our ability to pay dividends in the future.

Historically, we have paid quarterly common share dividends to our shareholders and quarterly distributions to our operating partnership unitholders, and we intend to continue to pay such dividends and distributions in amounts such that all or substantially all of our net taxable income in each year is distributed, which, along with other factors, should enable us to continue to qualify for the tax benefits accorded to a REIT under the Code. We have not established a minimum dividends payment level, and all future distributions will be made at the discretion of our board. Our ability to pay dividends, and the amount of any dividends we may pay, will depend upon, among other factors:

•the operational and financial performance of our properties;

•capital expenditures with respect to existing and newly acquired properties;

•general and administrative expenses associated with our operation as a publicly-held REIT;

•maintenance of our REIT qualification;

•the amount of, and the interest rates on, our debt and the ability to refinance our debt;

•the absence of significant expenditures relating to environmental, health or safety, or other regulatory matters; and

•other risk factors described in this Annual Report on Form 10-K.

Certain of these matters are beyond our control and any significant difference between our expectations and actual results could have a material adverse effect on our cash flow and our ability to make distributions to shareholders.

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Future offerings of debt or equity securities, which may rank senior to our common shares, may adversely affect the market price of our common shares.

If we decide to issue debt securities in the future, which would rank senior to our common shares, it is likely that they will be governed by an indenture or other instrument containing covenants restricting our operating flexibility. Additionally, any equity securities or convertible or exchangeable securities that we issue in the future may have rights, preferences and privileges more favorable than those of our common shares and may result in dilution to owners of such shares. We and, indirectly, our shareholders will bear the cost of issuing and servicing such securities. Because our decision to issue debt or equity securities in any future offering will depend on market conditions and other factors beyond our control, we cannot predict or estimate the amount, timing or nature of our future offerings. Thus, holders of our common shares will bear the risk of our future offerings reducing the market price of our shares and diluting the value of their common share holdings in us.

Item 1B. Unresolved Staff Comments

None.

Item 1C. Cybersecurity

Risk management and strategy

We recognize the critical importance of developing, implementing, and maintaining robust cybersecurity measures aligned to industry standards to safeguard our information systems and protect the confidentiality, integrity, and availability of our data.

Management of Material Risks & Integration into Overall Risk Management

We have strategically integrated cybersecurity risk management into our broader risk management framework to promote a company-wide culture of cybersecurity awareness and risk management and have incorporated cybersecurity considerations into our decision-making processes. Our risk management team works closely with our IT department to identify, evaluate and address cybersecurity risks in alignment with our business objectives and operational needs. Our risk management team also provides regular reporting to management on our enterprise cybersecurity risk posture.

Engagement of Third-parties on Risk Management

Recognizing the complexity and evolving nature of cybersecurity threats, we engage a range of external experts, including cybersecurity assessors and consultants in evaluating and testing our risk management systems. These partnerships enable us to leverage specialized knowledge and insights, so that we can better understand the current and evolving cybersecurity risks and strategies. Our collaboration with these third-parties includes periodic audits, threat assessments, and consultation on security enhancements.

Risks from Cybersecurity Threats

We are not aware of any risks from cybersecurity threats, including as a result of any cybersecurity incidents, which have materially affected or are reasonably likely to materially affect our Company, including our business strategy, results of operations, or financial condition. Refer to "Item 1A. Risk factors" in this annual report on Form 10-K, including "Security breaches through cyber-attacks, cyber-intrusions, or other methods could disrupt our information technology networks and related systems", for additional discussion about cybersecurity-related risks.

Governance

The board of trustees is acutely aware of the critical nature of managing risks associated with cybersecurity threats and oversees the Company's cybersecurity risk management activities.

Board of Trustees Oversight

The audit committee of our board of trustees is central to the board of trustees's oversight of cybersecurity risks and bears the primary responsibility for this domain. The members of the audit committee have a variety of expertise, including financial, regulatory and risk management. The audit committee reviews our policies with respect to risk assessment and risk management related to cybersecurity. The audit committee and the board of trustees receive updates on the Company's cybersecurity risks and initiatives periodically. In addition, cybersecurity matters are reported to the audit committee or board of trustees so that the board of trustees and audit committee can effectively carry out their oversight role.

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Management's Role Managing Risk

Our risk management committee is comprised of a cross section of the Company's management team. The risk management committee has identified cybersecurity as a key risk to the Company's operations and established a cybersecurity sub-committee, which is comprised of members of the risk management committee and other personnel, to focus on this risk.

The cybersecurity sub-committee plays a pivotal role in informing the risk management committee on cybersecurity risks. They provide comprehensive briefings to the risk management committee on a regular basis. These briefings encompass a broad range of topics, including:

•Awareness of cybersecurity landscape, emerging threats, trends and developments;

•Status of ongoing cybersecurity initiatives and strategies;

•Incident reports and learnings from any cybersecurity events;

•Compliance with regulatory requirements and industry standards; and

•Education in cybersecurity and associated risk management frameworks.

The risk management committee actively participates in strategic decisions related to cybersecurity, offering guidance and approval for major initiatives. This involvement ensures that cybersecurity considerations are a consistent focus of the Company and that the Company's cybersecurity efforts are aligned with the overall risk management framework. We have also implemented cybersecurity training at all levels of our organization and conduct periodic phishing assessment for our employees to reinforce that training.

Risk Management Personnel

Primary responsibility for assessing, monitoring and managing our cybersecurity risks rests with the cybersecurity sub-committee. With over a combined 50 years of experience in the field of cybersecurity, the cybersecurity sub-committee brings a wealth of expertise to their role. Their in-depth knowledge and experience are instrumental in developing and executing our cybersecurity strategies. Our cybersecurity sub-committee oversees our cybersecurity strategies, tests our compliance with standards, remediates known risks, and leads our employee training program.

Monitor Cybersecurity Incidents

The cybersecurity sub-committee stays apprised about the latest developments in cybersecurity, including potential threats and innovative risk management techniques, which is important for the effective prevention, detection, mitigation, and remediation of cybersecurity incidents. The cybersecurity sub-committee implements and oversees processes for the regular monitoring of our information systems. This includes the deployment of advanced security measures and regular system audits to identify potential vulnerabilities. In the event of a cybersecurity incident, the cybersecurity sub-committee is equipped with a well-defined incident response plan, which provides a framework to mitigate the impact of cybersecurity incidents.

The cybersecurity sub-committee regularly informs the risk management committee of matters related to cybersecurity risks and incidents. This ensures that the highest levels of management are kept abreast of the cybersecurity posture and potential risks facing the Company. Furthermore, significant cybersecurity matters and strategic risk management decisions are escalated to the audit committee and board of trustees, ensuring that they have comprehensive oversight and can provide guidance on critical cybersecurity issues.

Item 2. Properties

As of December 31, 2025, we held ownership interests in and operated a geographically diversified portfolio of 1,063 self storage properties located in 37 states and Puerto Rico, comprising approximately 69.4 million rentable square feet, configured in approximately 548,000 storage units, excluding three properties classified as held for sale that were sold to a third party in January 2026. Of these properties, we reported 801 wholly-owned self storage properties on a consolidated basis that contain approximately 51.1 million rentable square feet and we held a 25% ownership interest in 262 unconsolidated real estate venture properties that contain approximately 18.2 million rentable square feet.

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The following table sets forth summary information regarding our consolidated properties by state as of December 31, 2025.

Number of Number of Rentable % of Rentable Period-end

State/Territory Properties Units Square Feet Square Feet Occupancy

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The following table sets forth summary information regarding our unconsolidated real estate venture properties by state as of December 31, 2025.

Number of Number of Rentable % of Rentable Period-end

State Properties Units Square Feet Square Feet Occupancy

Our portfolio consists of self storage properties that are designed to offer customers convenient, affordable, and secure storage units. Generally, our properties are in highly visible locations clustered in states or markets with strong population and job growth and are specifically designed to accommodate residential and commercial tenants with features such as security systems, electronic gate entry, easy access, climate control, and pest control. Our units typically range from 25 square feet to 300 square feet, and some of our properties also offer outside storage for vehicles, boats, and equipment. We provide 24-hour access to many storage units through computer controlled access systems. Many of our properties are equipped with security cameras, and many individual storage units feature sprinkler systems. Almost all of the storage units in our portfolio are leased on a month-to-month basis providing us the flexibility to increase rental rates over time as market conditions permit. Additional information on our consolidated self storage properties is contained in "Schedule III - Real Estate and Accumulated Depreciation" in this Annual Report on Form 10-K.

Item 3. Legal Proceedings

We are not currently subject to any legal proceedings that we consider to be material.

Item 4. Mine Safety Disclosures

Not applicable.

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PART II

Item 5. Market for the Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Market Information

Our common shares have been listed and traded on the NYSE under the symbol "NSA" since April 22, 2015. Prior to that time there was no public market for our common shares.

Holders

As of February 20, 2026, we had 72 record holders of its common shares. The 72 holders of record do not include the beneficial owners of common shares whose shares are held by a broker or bank. Such information was obtained from our transfer agent and registrar.

Dividends

Since our initial quarter as a publicly-traded REIT, we have made regular quarterly distributions to our shareholders. Holders of common shares are entitled to receive distributions when declared by our board of trustees out of any assets legally available for that purpose. In order to maintain our status as a REIT for U.S. federal income tax purposes, we are required to distribute at least 90% of our "REIT taxable income," which is generally equivalent to our net taxable ordinary income, determined without regard to the deduction for dividends paid and excluding net capital gains to our shareholders annually.

Common share dividends are characterized for U.S. federal income tax purposes as ordinary income, capital gains, return of capital or a combination thereof. Each year we communicate to shareholders the tax characterization of the common share dividends paid during the preceding year. Our tax return for the year ended December 31, 2025 has not yet been filed and consequently, the taxability information presented for our dividends paid in 2025 is based upon management's estimate. The following table summarizes the estimated taxability of our dividends per common share for the year ended December 31, 2025:

Year Ended

Equity Compensation Plan Information

Information about our equity compensation plans is incorporated by reference to Item 12 of Part III of this Annual Report on Form 10-K.

Unregistered Sales of Equity Securities

During the three months ended December 31, 2025, the Company, in its capacity as general partner of its operating partnership, caused the operating partnership to issue 148,967 common shares to satisfy redemption requests from certain limited partners.

Following a specified lock up period after the date of issuance, the OP units issued by the operating partnership may be redeemed from time to time by holders for a cash amount per OP unit equal to the market value of an equivalent number of common shares. We have the right, but not the obligation, to assume and satisfy the redemption obligation of the operating partnership described above by issuing one common share in exchange for each OP unit tendered for redemption.

We may elect to report early the private placement of our common shares that may occur if we elect to assume the redemption obligation of the operating partnership as described above in the event that OP units are in the future tendered for redemption.

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As of February 20, 2026, other than those OP units held by the Company, after reflecting the transactions described herein, 57,495,864 OP units were outstanding (including 710,841 outstanding LTIP units in the operating partnership and 5,769,214 outstanding DownREIT OP units, which are convertible into, or exchangeable for, OP units on a one-for-one basis, subject to certain conditions).

These issuances were exempt from registration under Section 4(a)(2) of the Securities Act of 1933, as amended.

Issuer Purchases of Equity Securities

On July 11, 2022, we approved a share repurchase program authorizing the repurchase of up to $400.0 million of our common shares, under which $256,892 of common shares remain available for repurchase. On December 1, 2023, we approved a new share repurchase program authorizing, but not obligating, the repurchase of up to $275.0 million of our common shares, under which no common shares remain available for repurchase. On November 14, 2024, we approved a new share repurchase program authorizing, but not obligating, the repurchase of up to $350.0 million of our common shares. During the three months ended December 31, 2025, certain of our employees surrendered common shares owned by them to satisfy their statutory minimum federal and state tax obligations associated with the vesting of restricted shares issued to them. The table below summarizes all of our repurchases of common shares during the three months ended December 31, 2025:

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Performance Graph

The following chart compares the yearly cumulative total shareholder return for our common shares with the cumulative shareholder return of companies on (i) the S&P 500 Index, (ii) the Russell 2000 and (iii) the Nareit All Equity REIT Index as provided by Nareit for the period beginning December 31, 2020 and ending December 31, 2025.

Period Ending

The foregoing item assumes $100.00 invested on December 31, 2020, with dividends reinvested. The Performance Graph will not be deemed to be incorporated by reference into any filing by NSA under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except to the extent that NSA specifically incorporates the same by reference.

Item 6. [Reserved]

None.

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the financial statements and notes thereto included in Item 8. "Financial Statements and Supplementary Data" as well as Item 1. "Business," Item 1A. "Risk Factors," and Item 2. "Properties," respectively, in this Annual Report on Form 10-K.

Overview

National Storage Affiliates Trust is a fully integrated, self-administered and self-managed real estate investment trust organized in the state of Maryland on May 16, 2013. We have elected and we believe that we have qualified to be taxed as a REIT commencing with our taxable year ended December 31, 2015. We serve as the sole general partner of our operating partnership, a Delaware limited partnership formed on February 13, 2013 to conduct our business, which is focused on the ownership, operation, and acquisition of self storage properties located predominantly within the top 100 MSAs throughout the United States.

Our vice chairperson of the board of trustees and former chairperson of the board of trustees and chief executive officer, Arlen D. Nordhagen, co-founded SecurCare Self Storage, Inc. in 1988 to invest in and manage self storage properties. While growing SecurCare to over 150 self storage properties, Mr. Nordhagen recognized a market opportunity for a differentiated public self storage REIT that would leverage the benefits of national scale by integrating multiple experienced regional self storage operators with local operational focus and expertise, which we refer to as our former PRO structure. Although the PRO structure contributed significantly to our growth over the last decade, the internalization of the PRO structure, which occurred on July 1, 2024, was always a part of our long term vision. Over time, largely through our unconsolidated real estate ventures, retirement of PROs and the internalization of our PRO structure, we have developed a full service internally-staffed property management platform.

Our Structure

Through our property management platform, we direct, manage and control the day-to-day operations and affairs of our consolidated properties and our unconsolidated real estate ventures. As of December 31, 2025, our property management platform managed and controlled substantially all of our 801 consolidated properties and 262 of our unconsolidated real estate venture properties. The properties are primarily managed by us under the brands of iStorage, Move It, Northwest, RightSpace, SecurCare and Southern.

We earn certain customary fees for managing and operating the properties in the unconsolidated real estate ventures and we facilitate tenant insurance and/or tenant warranty protection programs for tenants at these properties in exchange for half of all proceeds from such programs.

Our Consolidated Properties

We seek to own properties that are well located in high quality sub-markets with highly accessible street access and attractive supply and demand characteristics, providing our properties with strong and stable cash flows that are less sensitive to the fluctuations of the general economy. Many of these markets have multiple barriers to entry against increased supply, including zoning restrictions against new construction and new construction costs that we believe are higher than our properties' fair market value. We maintain an active acquisition pipeline that we expect will continue to drive our future growth.

As of December 31, 2025, we owned a geographically diversified portfolio of 801 self storage properties, located in 33 states and Puerto Rico, comprising approximately 51.1 million rentable square feet, configured in approximately 403,000 storage units.

Our Unconsolidated Real Estate Ventures

We seek to opportunistically partner with institutional funds and other institutional investors and other third parties to acquire attractive portfolios which may utilize a promoted return structure. We believe there is significant opportunity for continued external growth by partnering with institutional investors or other third parties seeking to deploy capital in the self storage industry.

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2024 Joint Venture

As of December 31, 2025, our 2024 Joint Venture, in which we have a 25% ownership interest, owned and operated 56 self storage properties containing approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units and located across seven states.

2023 Joint Venture

As of December 31, 2025, our 2023 Joint Venture, in which we have a 25% ownership interest, owned and operated 21 self storage properties containing approximately 1.4 million rentable square feet, configured in approximately 9,000 storage units and located across five states.

2018 Joint Venture

As of December 31, 2025, our 2018 Joint Venture, in which we have a 25% ownership interest, owned and operated 104 self storage properties containing approximately 7.9 million rentable square feet, configured in approximately 65,000 storage units and located across 17 states.

2016 Joint Venture

As of December 31, 2025, our 2016 Joint Venture, in which we have a 25% ownership interest, owned and operated 81 properties containing approximately 5.7 million rentable square feet, configured in approximately 47,000 storage units and located across 13 states.

IRE Investment

As of December 31, 2025, we had entered into an agreement with an affiliate of Investment Real Estate Management, LLC (the "IRE Member") to form a new venture to acquire self storage properties (the "IRE Investment"), whereby we committed to provide 75% of the equity capital, up to a maximum of $105.0 million in cash in exchange for preferred equity, and the IRE Member committed to provide 25% of the equity capital, up to a maximum of $35.0 million in cash in exchange for common equity. An affiliate of the IRE Member will serve as the manager of the IRE Investment and will manage the day-to-day operations of the self storage properties. As of December 31, 2025 the IRE Investment did not own any self storage properties.

Results of Operations

When reviewing our results of operations it is important to consider the timing of acquisition and disposition activity. We acquired four self storage properties, two annexes to existing properties and disposed of 15 self storage properties to unaffiliated third parties during the year ended December 31, 2025. During the year ended December 31, 2024, we contributed 56 self storage properties to the 2024 Joint Venture, sold an additional 40 self storage properties and acquired seven self storage properties. As a result of these and other factors, we do not believe that our historical results of operations discussed and analyzed below are comparable or necessarily indicative of our future results of operations or cash flows.

The following discussion and analysis of the results of our operations and financial condition for the year ended December 31, 2025 compared to the year ended December 31, 2024 should be read in conjunction with the accompanying consolidated financial statements included in Item 8. The discussion and analysis of the results of our operations and financial condition for the year ended December 31, 2024 compared to the year ended December 31, 2023, can be found in Part II, "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" of our Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on February 27, 2025.

Certain figures, such as interest rates and other percentages, included in this section have been rounded for ease of presentation. Percentage figures included in this section have not in all cases been calculated on the basis of such rounded figures but on the basis of such amounts prior to rounding. For this reason, percentage amounts in this section may vary slightly from those obtained by performing the same calculations using the figures in our consolidated financial statements or in the associated text. Certain other amounts that appear in this section may similarly not sum due to rounding.

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Year Ended December 31, 2025 compared to the Year Ended December 31, 2024

Overview

The following table illustrates the changes in rental revenue, other property-related revenue, management fees and other revenue, property operating expenses, and other expenses for the year ended December 31, 2025 compared to the year ended December 31, 2024 (dollars in thousands):

Year Ended December 31,

Other (expense) income

Loss on early extinguishment of debt — (323) 323

Net income attributable to noncontrolling interests (42,490) (71,752) 29,262

Distributions to preferred shareholders (20,462) (20,445) (17)

Total Revenue

Our total revenue, including management fees and other revenue, decreased by $17.4 million, or 2.3%, for the year ended December 31, 2025, as compared to the year ended December 31, 2024. This decrease was primarily attributable to a decrease in total portfolio average occupancy from 85.6% for the year ended December 31, 2024 to 83.8% for the year ended December 31, 2025. The decrease in total revenue was also attributable to the sale of 55 self storage properties to unaffiliated third parties between January 1, 2024 and December 31, 2025, and the contribution of 56 self storage properties to the 2024 Joint Venture during the three months ended March 31, 2024. Average occupancy is calculated based on the average of the month-end occupancy immediately preceding the period presented and the month-end occupancies included in the respective period presented.

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Rental Revenue

Rental revenue decreased by $21.8 million, or 3.1%, for the year ended December 31, 2025, as compared to the year ended December 31, 2024. The decrease in rental revenue was primarily attributable to (i) a decrease in total portfolio average occupancy from 85.6% for the year ended December 31, 2024 to 83.8% for the year ended December 31, 2025, (ii) the sale of 55 self storage properties to unaffiliated third parties between January 1, 2024 and December 31, 2025, and (iii) the contribution of 56 self storage properties to the 2024 Joint Venture during the three months ended March 31, 2024. Annualized total portfolio rental revenues (including fees and net of any discounts and uncollectible customer amounts) divided by average occupied square feet ("average annualized rental revenue per occupied square foot") increased from $15.61, for the year ended December 31, 2024 to $15.63, or 0.1%, for the year ended December 31, 2025.

Other Property-Related Revenue

Other property-related revenue represents ancillary income from our self storage properties, such as tenant insurance-related access fees and sales of storage supplies. Other property-related revenue decreased by $1.5 million, or 5.3%, for the year ended December 31, 2025, as compared to the year ended December 31, 2024. This decrease primarily resulted from a decrease in ancillary income due to the disposition of properties between January 1, 2024 and December 31, 2025.

Management Fees and Other Revenue

Management fees and other revenue, which includes revenue related to managing and operating the unconsolidated real estate ventures and other revenue from our tenant insurance programs, increased $5.8 million, or 13.6%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. This increase was primarily attributable to an increase in tenant insurance activity upon our acquisition of certain rights related to certain former PROs' tenant insurance-related programs as part of the internalization of the PRO structure during the year ended December 31, 2024.

Property Operating Expenses

Property operating expenses increased by $5.7 million, or 2.7%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. The increase in property operating expenses was primarily attributable to increases in marketing, repairs and maintenance, and property tax expense, partially offset by decreases in property operating expenses resulting from the sale of 55 self storage properties to unaffiliated third parties between January 1, 2024 and December 31, 2025, and the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024.

General and Administrative Expenses

General and administrative expenses decreased by $6.5 million, or 11.2%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. This result was primarily attributable to a decrease in management fees following the internalization of the PRO structure during the year ended December 31, 2024.

Depreciation and Amortization

Depreciation and amortization decreased $0.5 million, or 0.3%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. This decrease was primarily attributable to a decrease in self storage property related depreciation, partially offset by an increase in amortization expense related to intangible assets.

Other

Other expenses increased $2.4 million, or 17.5%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. This increase was primarily attributable to increases in administrative costs relating to our tenant insurance programs, due to an increase in related activity upon our acquisition of certain rights related to certain former PROs' tenant insurance-related programs as part of the internalization of the PRO structure during the year ended December 31, 2024.

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Interest Expense

Interest expense increased $8.2 million, or 5.3%, for the year ended December 31, 2025, compared to the year ended December 31, 2024. The increase in interest expense was primarily attributable to interest rate swaps that matured in August 2024 and February 2025. The maturity of these swaps, which effectively fixed SOFR at a lower rate than the prevailing market rate, resulted in an increase in the amount of debt subject to variable interest rates (excluding variable-rate debt subject to interest rate swaps) outstanding from $223.3 million, as of December 31, 2024, to $405.9 million as of December 31, 2025.

Loss on Early Extinguishment of Debt

Loss on early extinguishment of debt decreased $0.3 million for the year ended December 31, 2025, compared to the year ended December 31, 2024. During the year ended December 31, 2024, in connection with the early repayment of Term Loan C, we expensed $0.3 million of unamortized debt issuance costs.

Equity In (Losses) Earnings Of Unconsolidated Real Estate Ventures

Equity in (losses) earnings of unconsolidated real estate ventures represents our share of earnings and losses incurred through our 25% ownership interests in the 2024 Joint Venture, 2023 Joint Venture, 2018 Joint Venture and the 2016 Joint Venture. During the year ended December 31, 2025, we recorded $7.3 million of equity in losses from our unconsolidated real estate ventures compared to $16.1 million in losses for the year ended December 31, 2024. The decrease was primarily attributable to the non-cash impact of applying the hypothetical liquidation at book value ("HLBV") method to the 2024 Joint Venture, which allocates income (loss) based on the change in each owners' claim on net assets upon a hypothetical liquidation of the underlying joint venture at book value as of December 31, 2025.

Acquisition and Integration Costs

Acquisition and integration costs increased $3.1 million for the year ended December 31, 2025, compared to the year ended December 31, 2024. This increase was primarily attributable to costs related to the internalization of the PRO structure.

Gain on Sale of Self Storage Properties

Gain on sale of self storage properties was $16.3 million, for the year ended December 31, 2025, compared to $63.8 million for the year ended December 31, 2024.

Net Income Attributable to Noncontrolling Interests

Net income attributable to noncontrolling interests was $42.5 million for the year ended December 31, 2025, compared to $71.8 million for the year ended December 31, 2024.

Critical Accounting Policies and Use of Estimates

Our financial statements have been prepared on the accrual basis of accounting in accordance with GAAP. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates and assumptions, including those that impact our most critical accounting policies. We base our estimates and assumptions on historical experience and on various other factors that we believe are reasonable under the circumstances. Our critical accounting estimates are defined as accounting estimates or assumptions made in accordance with GAAP, which involve a significant level of estimation, uncertainty or subjectivity and have had or are reasonably likely to have a material impact on our financial condition or results of operations. Actual results may differ from these estimates. We believe the following are our most critical accounting policies.

Principles of Consolidation and Presentation of Noncontrolling Interests

Our consolidated financial statements include the accounts of our operating partnership and its controlled subsidiaries. All significant intercompany balances and transactions have been eliminated in the consolidation of entities.

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The limited partner ownership interests in our operating partnership that are held by owners other than us are referred to as noncontrolling interests. Noncontrolling interests also include ownership interests in DownREIT partnerships held by entities other than our operating partnership. Noncontrolling interests in a subsidiary are generally reported as a separate component of equity in our consolidated balance sheets. In our consolidated statements of operations, the revenues, expenses and net income or loss related to noncontrolling interests in our operating partnership are included in the consolidated amounts, with net income or loss attributable to the noncontrolling interests deducted separately to arrive at the net income or loss solely attributable to us.

When we obtain an economic interest in an entity, we evaluate the entity to determine if the entity is deemed a variable interest entity ("VIE"), and if we are deemed to be the primary beneficiary, in accordance with authoritative guidance issued on the consolidation of VIEs. When an entity is not deemed to be a VIE, we consider the provisions of additional guidance to determine whether the general partner controls a limited partnership or similar entity when the limited partners have certain rights. We consolidate all entities that are VIEs and of which the Company is deemed to be the primary beneficiary.

Self Storage Properties and Customer In-Place Leases

Self storage properties are carried at historical cost less accumulated depreciation and any impairment losses. When self storage properties are acquired, the purchase price is allocated to the tangible and intangible assets acquired and liabilities assumed based on estimated fair values. The purchase price is allocated to the individual properties based on the fair value determined using an income approach or a cash flow analysis using appropriate risk adjusted capitalization rates, which take into account the relative size, age, and location of the individual properties along with current and projected occupancy and relative rental rates or appraised values, if available. Tangible assets are allocated to land, buildings and related improvements, and furniture and equipment.

In allocating the purchase price for a self storage property acquisition, we determine whether the acquisition includes intangible assets. We allocate a portion of the purchase price to an intangible asset attributed to the value of customer in-place leases. Because the majority of tenant leases are on a month-to-month basis, this intangible asset represents the estimated value of the leases in effect on the acquisition date. This intangible asset is amortized to expense using the straight-line method over 12 months, the estimated average remaining rental period for the leases.

Non-GAAP Financial Measures

FFO and Core FFO

Funds from operations, or FFO, is a widely used performance measure for real estate companies and is provided here as a supplemental measure of our operating performance. The December 2018 Nareit Funds From Operations White Paper - 2018 Restatement defines FFO as net income (as determined under GAAP), excluding: real estate depreciation and amortization, gains and losses from the sale of certain real estate assets, gains and losses from change in control, mark-to-market changes in value recognized on equity securities, impairment write-downs of certain real estate assets and impairment of investments in entities when it is directly attributable to decreases in the value of depreciable real estate held by the entity, and after adjusting equity in earnings (losses) to reflect our share of FFO in unconsolidated real estate ventures. Distributions declared on subordinated performance units and DownREIT subordinated performance units represented our allocation of FFO to noncontrolling interests held by subordinated performance unitholders and DownREIT subordinated performance unitholders. For purposes of calculating FFO attributable to common shareholders, OP unitholders, and LTIP unitholders, we exclude distributions declared on preferred shares and preferred units, and, prior to the internalization of the PRO structure, subordinated performance units and DownREIT subordinated performance units. We define Core FFO as FFO, as further adjusted to eliminate the impact of certain items that we do not consider indicative of our core operating performance. These further adjustments consist of acquisition costs, integration costs, executive severance costs, gains on debt forgiveness, gains (losses) on early extinguishment of debt, casualty-related expenses, losses, and related recoveries and adjustments for unconsolidated partnerships and joint ventures.

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Management uses FFO and Core FFO as key performance indicators in evaluating the operations of our properties. Given the nature of our business as a real estate owner and operator, we consider FFO and Core FFO as key supplemental measures of our operating performance that are not specifically defined by GAAP. We believe that FFO and Core FFO are useful to management and investors as a starting point in measuring our operational performance because FFO and Core FFO exclude various items included in net income (loss) that do not relate to or are not indicative of our operating performance such as gains (or losses) from sales of self storage properties and depreciation, which can make periodic and peer analyses of operating performance more difficult. Our computation of FFO and Core FFO may not be comparable to FFO reported by other REITs or real estate companies.

FFO and Core FFO should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with GAAP, such as total revenues, operating income and net income (loss). FFO and Core FFO do not represent cash generated from operating activities determined in accordance with GAAP and are not a measure of liquidity or an indicator of our ability to make cash distributions. We believe that to further understand our performance, FFO and Core FFO should be compared with our reported net income (loss) and considered in addition to cash flows computed in accordance with GAAP, as presented in our consolidated financial statements.

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The following table presents a reconciliation of net income to FFO and Core FFO for the periods presented (in thousands, except per share and unit amounts):

Year Ended December 31,

Add (subtract):

FFO attributable to subordinated performance unitholders(1) — (21,622) (49,040)

Add (subtract):

Integration and executive severance costs(2) 4,762 2,671 —

Casualty-related recoveries(3) — — (522)

Loss on early extinguishment of debt — 323 758

Weighted average shares and units outstanding - FFO and Core FFO:(4)

Weighted average restricted common shares outstanding 23 20 25

Weighted average DownREIT OP unit equivalents outstanding 5,769 3,955 2,120

Weighted average LTIP units outstanding 878 684 553

Core FFO per share and unit $ 2.23 $ 2.44 $ 2.69

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The following table presents a reconciliation of earnings per share - diluted to FFO and Core FFO per share and unit for the periods presented:

Year Ended December 31,

Earnings per share - diluted $ 0.69 $ 1.18 $ 1.48

Add real estate depreciation and amortization 1.38 1.49 1.73

Add Company's share of FFO in unconsolidated real estate ventures 0.17 0.19 0.19

Subtract gain on sale of self storage properties (0.12) (0.50) (0.52)

FFO attributable to subordinated performance unitholders — (0.17) (0.38)

Add integration and executive severance costs 0.04 0.02 —

Add loss on early extinguishment of debt — — 0.01

Core FFO per share and unit $ 2.23 $ 2.44 $ 2.69

Net Operating Income

Net operating income, or NOI, represents rental revenue plus other property-related revenue less property operating expenses. NOI is not a measure of performance calculated in accordance with GAAP.

We believe NOI is useful to investors in evaluating our operating performance because:

•NOI is one of the primary measures used by our management to evaluate the economic productivity of our properties, including our ability to lease our properties, increase pricing and occupancy and control our property operating expenses;

•NOI is widely used in the real estate industry and the self storage industry to measure the performance and value of real estate assets without regard to various items included in net income that do not relate to or are not indicative of operating performance, such as depreciation and amortization, which can vary depending upon accounting methods, the book value of assets, and the impact of our capital structure; and

•We believe NOI helps our investors to meaningfully compare the results of our operating performance from period to period by removing the impact of our capital structure (primarily interest expense on our outstanding indebtedness) and depreciation of the cost basis of our assets from our operating results.

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There are material limitations to using a non-GAAP measure such as NOI, including the difficulty associated with comparing results among more than one company and the inability to analyze certain significant items, including depreciation and interest expense, that directly affect our net income (loss). We compensate for these limitations by considering the economic effect of the excluded expense items independently as well as in connection with our analysis of net income (loss). NOI should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with GAAP, such as total revenues and net income (loss).

As of December 31, 2025, our same store portfolio consisted of 771 self storage properties. Our same store portfolio is defined as those properties owned and operated since the first day of the earliest year presented, excluding any properties sold, expected to be sold or subject to significant changes such as expansions or casualty events which cause the portfolio's year-over-year operating results to no longer be comparable. The following table illustrates the changes in rental revenue, other property-related revenue, and property operating expenses, for the year ended December 31, 2025 compared to the year ended December 31, 2024 (dollars in thousands):

Year Ended December 31,

Rental revenue

Other property-related revenue

Property operating expenses

Prior period comparability adjustment(1) — (1,443) 1,443

Net operating income

Rental Revenue

Source: SEC EDGAR (public domain) · 10-K for the period ended 2025-12-31, filed 2026-02-26 · accession 0001628280-26-012248

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