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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. Although the PRO structure significantly contributed to our growth over the last decade, the internalization of the PRO structure has always been a part of our long term vision. Our former structure offered our former PROs a unique opportunity to serve as regional property managers for their managed portfolios and directly participate in the potential upside of those properties while simultaneously diversifying their investment to include a broader portfolio of self storage properties. Over time, largely through our unconsolidated real estate ventures, retirement of PROs and internalization of the PRO structure, effective as of the Closing Date, we have developed a full service internally-staffed property management platform.

As a result of the internalization of the PRO structure, we purchased each of the PROs' management contracts, certain PRO IP, and certain rights with respect to the PROs' tenant insurance programs. We have transitioned the majority of operations in a phased approach, which is expected to continue over the 12 month period following the Closing Date, and we have executed new asset management and property management agreements with a number of our former PROs for all or a part of this transitionary period at newly negotiated management fees. In connection with the internalization, on the Closing Date, all 11,906,167 outstanding subordinated performance units and DownREIT subordinated performance units were converted into an aggregate of 17,984,787 OP units and DownREIT OP units.

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, 2024, our property management platform managed and controlled the majority of our 815 consolidated properties and all 259 of our unconsolidated real estate venture properties. The properties are primarily managed by us under the brands of iStorage, Move It, Moove In, 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.

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As of December 31, 2024, we owned a geographically diversified portfolio of 815 self storage properties, located in 38 states and Puerto Rico, comprising approximately 52.2 million rentable square feet, configured in approximately 409,000 storage units. Of these properties, 306 were acquired by us from our former PROs, 508 were acquired by us from unaffiliated third-party sellers and one was acquired by us from the 2016 Joint Venture.

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.

2024 Joint Venture

As of December 31, 2024, 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, 2024, our 2023 Joint Venture, in which we have a 25% ownership interest, owned and operated 18 self storage properties, all of which were acquired by the 2023 Joint Venture in 2024, containing approximately 1.2 million rentable square feet, configured in approximately 8,000 storage units and located across two states.

2018 Joint Venture

As of December 31, 2024, 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, 2024, 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.

Results of Operations

When reviewing our results of operations it is important to consider the timing of acquisition and disposition activity and the internalization of our PRO structure. We contributed 56 self storage properties to the 2024 Joint Venture and sold an additional 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024. We also sold 32 self storage properties to an unaffiliated third party during the three months ended December 31, 2023. We acquired seven self storage properties during the year ended December 31, 2024 and 20 self storage properties during the year ended December 31, 2023. 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, 2024 compared to the year ended December 31, 2023 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, 2023 compared to the year ended December 31, 2022, 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, 2023, which was filed with the SEC on February 28, 2024.

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, 2024 compared to the Year Ended December 31, 2023

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, 2024 compared to the year ended December 31, 2023 (dollars in thousands):

Year Ended December 31,

Other (expense) income

Loss on early extinguishment of debt (323) (758) 435

Net income attributable to noncontrolling interests (71,752) (80,319) 8,567

Total Revenue

Our total revenue, including management fees and other revenue, decreased by $87.7 million, or 10.2%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. This decrease was primarily attributable to (i) the sale of 32 self storage properties to an unaffiliated third party in the three months ended December 31, 2023, (ii) the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024, and (iii) the sale of 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024. The decrease in total revenue was also attributable to a decrease in total portfolio average occupancy from 88.0% for the year ended December 31, 2023 to 85.6% for the year ended December 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 $93.7 million, or 11.8%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. The decrease in rental revenue was primarily attributable to (i) the sale of 32 self storage properties to an unaffiliated third party in the three months ended December 31, 2023, (ii) the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024, and (iii) the sale of 40 self storage properties to unaffiliated third parties during the year ended December 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 $15.24, for the year ended December 31, 2023 to $15.61, or 2.4%, for the year ended December 31, 2024, driven primarily by increased contractual lease rates for in-place tenants.

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 $2.3 million, or 7.8%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. This decrease primarily resulted from a decrease in tenant insurance revenue due to the disposition of properties during the three months ended December 31, 2023 and the year ended December 31, 2024.

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 $8.3 million, or 24.2%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. This increase was primarily attributable to increased property management and acquisition fees resulting from the 2023 Joint Venture and the 2024 Joint Venture and an increase in tenant insurance activity upon our acquisition of certain rights related to certain former PROs’ tenant insurance-related programs during the year ended December 31, 2024.

Property Operating Expenses

Property operating expenses decreased by $17.1 million, or 7.5%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. The decrease in property operating expenses was primarily attributable to (i) the sale of 32 self storage properties to an unaffiliated third party in the three months ended December 31, 2023, (ii) the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024, and (iii) the sale of 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024.

General and Administrative Expenses

General and administrative expenses decreased by $1.7 million, or 2.8%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. This result was primarily attributable to a decrease in management fees following the internalization of the PRO structure.

Depreciation and Amortization

Depreciation and amortization decreased $32.1 million, or 14.5%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. This decrease was primarily attributable to (i) the sale of 32 self storage properties to an unaffiliated third party in the three months ended December 31, 2023, (ii) the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024, and (iii) the sale of 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024.

Other

Other expenses increased $2.8 million, or 24.8%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. 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 during the year ended December 31, 2024.

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Interest Expense

Interest expense decreased $11.9 million, or 7.2%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. The decrease in interest expense was primarily attributable to a decrease in the amount of debt subject to variable interest rates (excluding variable-rate debt subject to interest rate swaps) outstanding from $511.0 million, as of December 31, 2023, to $223.3 million as of December 31, 2024.

Loss on Early Extinguishment of Debt

Loss on early extinguishment of debt decreased $0.4 million, or 57.4%, for the year ended December 31, 2024, compared to the year ended December 31, 2023. 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. During the year ended December 31, 2023, in connection with an amendment to our credit facility, two of the lenders that were included in the syndicated group of lenders prior to the amendment are no longer participating lenders following the amendment, which constitutes an extinguishment of debt for accounting purposes. Additionally, in connection with the amendment we retired two term loans prior to their contractual maturity. Loss on early extinguishment of debt includes costs incurred related to these extinguishments, and the write off of $0.4 million of unamortized debt issuance costs related to the retired term loans or attributed to the entities no longer included in the lender syndicate.

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, 2024, we recorded $16.1 million of equity in losses from our unconsolidated real estate ventures compared to $7.6 million of earnings for the year ended December 31, 2023. 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, 2024.

Gain on Sale of Self Storage Properties

Gain on sale of self storage properties was $63.8 million, for the year ended December 31, 2024, compared to $63.9 million for the year ended December 31, 2023.

Net Income Attributable to Noncontrolling Interests

Net income attributable to noncontrolling interests was $71.8 million for the year ended December 31, 2024, compared to $80.3 million for the year ended December 31, 2023.

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):

Add (subtract):

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

Casualty-related (recoveries) expenses(3) — (522) 6,388

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 20 25 27

Weighted average DownREIT OP unit equivalents outstanding 3,955 2,120 1,925

Weighted average LTIP units outstanding 684 553 514

Core FFO per share and unit $ 2.44 $ 2.69 $ 2.81

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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 $ 1.18 $ 1.48 $ 0.99

Add real estate depreciation and amortization 1.49 1.73 1.79

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

Subtract gain on sale of self storage properties (0.50) (0.52) (0.05)

FFO attributable to subordinated performance unitholders (0.17) (0.38) (0.46)

Add integration and executive severance costs 0.02 — —

Add casualty-related expenses — — 0.05

Add loss on early extinguishment of debt — 0.01 —

Core FFO per share and unit $ 2.44 $ 2.69 $ 2.81

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, 2024, our same store portfolio consisted of 776 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, 2024 compared to the year ended December 31, 2023 (dollars in thousands):

Year Ended December 31,

Rental revenue

Other property-related revenue

Property operating expenses

Net operating income

Rental Revenue

Same store portfolio rental revenues decreased $22.4 million, or 3.2%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. This decrease in same store portfolio rental revenue was driven primarily by a decrease in average occupancy from 88.7% for the year ended December 31, 2023 to 85.8% for the year ended December 31, 2024. Average annualized same store rental revenue per occupied square foot decreased from $15.71 to $15.68, or 0.2%, for the year ended December 31, 2024, driven primarily by decreased lease rates for new tenants.

Other Property-Related Revenue

Same store portfolio other property-related revenue increased $0.6 million, or 2.5%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. This increase primarily resulted from an increase in tenant insurance revenue.

Property Operating Expenses

Same store portfolio property operating expenses increased $7.2 million, or 3.7%, for the year ended December 31, 2024, as compared to the year ended December 31, 2023. The increase in same store property operating expenses was a result of increases in marketing, insurance and property tax expense, partially offset by decreases in personnel costs and repairs and maintenance expenses during the year ended December 31, 2024.

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The following table presents a reconciliation of net income to NOI for the periods presented (dollars in thousands):

Year Ended December 31,

(Subtract) add:

Loss on early extinguishment of debt 323 758 —

Our consolidated NOI shown in the table above does not include our proportionate share of NOI for our unconsolidated real estate ventures. For additional information about our 2016 Joint Venture, 2018 Joint Venture, 2023 Joint Venture and 2024 Joint Venture see Note 5 to the consolidated financial statements in Item 8.

EBITDA and Adjusted EBITDA

We define EBITDA as net income (loss), as determined under GAAP, plus interest expense, loss on early extinguishment of debt, income taxes, depreciation and amortization expense and the Company's share of unconsolidated real estate venture depreciation and amortization. We define Adjusted EBITDA as EBITDA plus acquisition costs, integration costs, executive severance costs, equity-based compensation expense, losses on sale of properties, impairment of long-lived assets and casualty-related expenses, losses and recoveries, minus gains on sale of properties and debt forgiveness, and after adjustments for unconsolidated partnerships and joint ventures, including the removal of the non-cash effect of applying HLBV for purposes of allocating GAAP net income (loss) for the 2024 Joint Venture. These further adjustments eliminate the impact of items that we do not consider indicative of our core operating performance. In evaluating EBITDA and Adjusted EBITDA, you should be aware that in the future we may incur expenses that are the same as or similar to some of the adjustments in this presentation. Our presentation of EBITDA and Adjusted EBITDA should not be construed as an inference that our future results will be unaffected by unusual or non-recurring items.

We present EBITDA and Adjusted EBITDA because we believe they assist investors and analysts in comparing our performance across reporting periods on a consistent basis by excluding items that we do not believe are indicative of our core operating performance. EBITDA and Adjusted EBITDA have limitations as an analytical tool. Some of these limitations are:

•EBITDA and Adjusted EBITDA do not reflect our cash expenditures, or future requirements, for capital expenditures, contractual commitments or working capital needs;

•EBITDA and Adjusted EBITDA do not reflect the significant interest expense, or the cash requirements necessary to service interest or principal payments, on our debts;

•although depreciation and amortization are non-cash charges, the assets being depreciated and amortized will often have to be replaced in the future, and EBITDA and Adjusted EBITDA do not reflect any cash requirements for such replacements;

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•Adjusted EBITDA excludes equity-based compensation expense, which is and will remain a key element of our overall long-term incentive compensation package, although we exclude it as an expense when evaluating our ongoing operating performance for a particular period;

•EBITDA and Adjusted EBITDA do not reflect the impact of certain cash charges resulting from matters we consider not to be indicative of our ongoing operations; and

•other companies in our industry may calculate EBITDA and Adjusted EBITDA differently than we do, limiting their usefulness as comparative measures.

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). EBITDA and Adjusted EBITDA 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).

The following table presents a reconciliation of net income to EBITDA and Adjusted EBITDA for the periods presented (dollars in thousands):

Year Ended December 31,

Add:

Loss on early extinguishment of debt 323 758 —

Add (subtract):

Casualty-related (recoveries) expenses(3) — (522) 6,388

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Liquidity and Capital Resources

Liquidity Overview

Liquidity is the ability to meet present and future financial obligations. Our primary source of liquidity is cash flow from our operations. Additional sources are proceeds from dispositions of self storage properties (including contributions to our joint ventures), equity and debt offerings, debt financings including additional borrowing capacity under the credit facility, and expansion options available under the 2028 Term Loan Facility, the June 2029 Term Loan Facility, and our credit facility.

Our short-term liquidity requirements consist primarily of property operating expenses, property acquisitions, capital expenditures, general and administrative expenses and principal and interest on our outstanding indebtedness. A further short-term liquidity requirement relates to distributions to our common and preferred shareholders and holders of preferred units, OP units, LTIP units and DownREIT OP units. We expect to fund short-term liquidity requirements from our operating cash flow, cash on hand and borrowings under our credit facility.

Our long-term liquidity needs consist primarily of the repayment of debt, property acquisitions, and capital expenditures. We acquire properties through the use of cash, preferred units, and OP units in our operating partnership or DownREIT partnerships. We expect to meet our long-term liquidity requirements with operating cash flow, cash on hand, secured and unsecured indebtedness, and the issuance of equity and debt securities.

The availability of credit and its related effect on the overall economy may affect our liquidity and future financing activities, both through changes in interest rates and access to financing. In 2022 and 2023, the Federal Reserve Board increased interest rates from historically low levels, until pausing increases in August 2023 and decreasing rates in September 2024. Although the Federal Reserve Board has signaled an intention to continue to reduce interest rates in 2025, there is no assurance that this will occur or that the Federal Reserve Board will not maintain or raise interest rates in the future. Our ability to access capital on favorable terms as well as to use cash from operations to continue to meet our liquidity needs, all of which are highly uncertain and cannot be predicted, could be affected by various risks and uncertainties. We believe that, as a publicly-traded REIT, we will have access to multiple sources of capital to fund our long-term liquidity requirements, including the incurrence of additional debt and the issuance of debt and additional equity securities. However, we cannot assure you that this will be the case.

Cash Flows

At December 31, 2024, we had $50.4 million in cash and cash equivalents and $0.3 million of restricted cash, a decrease in cash and cash equivalents of $14.6 million and a decrease in restricted cash of $22.4 million from December 31, 2023. Restricted cash primarily consists of escrowed funds deposited with financial institutions for real estate taxes, insurance, and other reserves for capital improvements in accordance with our loan agreements. The following discussion relates to changes in cash due to operating, investing, and financing activities, which are presented in our consolidated statements of cash flows included in Item 8 of this report.

Operating Activities

Cash provided by our operating activities was $363.1 million for the year ended December 31, 2024 compared to $441.6 million the year ended December 31, 2023. Our operating cash flow decreased primarily due to a decrease in rental revenue, partially offset by a decrease in property operating expenses driven by (i) the sale of 32 self storage properties to an unaffiliated third party in the three months ended December 31, 2023, (ii) the contribution of 56 self storage properties to the 2024 Joint Venture in the three months ended March 31, 2024, and (iii) the sale of 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024.

Investing Activities

Cash provided by investing activities was $425.4 million for the year ended December 31, 2024 compared to $161.1 million of cash provided by investing activities for the year ended December 31, 2023. The primary sources of cash for the year ended December 31, 2024 were $616.8 million from the contribution of 56 self storage properties to the 2024 Joint Venture and the sale of 40 self storage properties to unaffiliated third parties during the year ended December 31, 2024, partially offset by our investment in the 2023 and 2024 Joint Ventures of $74.2 million, our acquisition of seven self storage properties for cash consideration of $64.6 million, our acquisition of intangible assets in connection with the internalization of our PRO structure for $32.7 million, and expenditures for corporate furniture and equipment of $1.9 million.

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Cash provided by investing activities was $161.1 million for the year ended December 31, 2023 compared to $584.2 million of cash used in investing activities for the year ended December 31, 2022. The primary sources of cash for the year ended December 31, 2023 were $262.3 million of proceeds from our sale of 32 self storage properties to an unaffiliated third party, partially offset by our acquisition of 20 self storage properties and annexes to existing properties for cash consideration of $48.7 million, capital expenditures of $34.2 million, our acquisition of management company assets and an interest in a reinsurance company of $16.9 million and expenditures for corporate furniture and equipment of $1.3 million.

Capital expenditures totaled $18.7 million, $34.2 million and $42.8 million during the years ended December 31, 2024, 2023 and 2022 respectively. We generally fund post-acquisition capital additions from cash provided by operating activities.

We categorize our capital expenditures broadly into three primary categories:

•recurring capital expenditures, which represent the portion of capital expenditures that are deemed to replace the consumed portion of acquired capital assets and extend their useful life;

•value enhancing capital expenditures, which represent the portion of capital expenditures that are made to enhance the revenue and value of an asset from its original purchase condition; and

•acquisitions capital expenditures, which represent the portion of capital expenditures capitalized during the current period that were identified and underwritten prior to a property's acquisition.

The following table presents a summary of the capital expenditures for these categories, along with a reconciliation of the total for these categories to the capital expenditures reported in the accompanying consolidated statements of cash flows for the periods presented (dollars in thousands):

Year Ended December 31,

Change in accrued capital spending 957 1,260 57

Financing Activities

Cash used in our financing activities was $825.4 million for the year ended December 31, 2024 compared to $557.2 million of cash used in financing activities for the year ended December 31, 2023. Our primary uses of financing cash flows for the year ended December 31, 2024 were for principal payments on existing debt of $1.5 billion (which included $857.7 million of principal repayments under the Revolver, $275.0 million repayment of Term Loan B, $325.0 million repayment of Term Loan C, $19.9 million of fixed rate mortgage repayments and $2.1 million of scheduled fixed rate mortgage principal amortization payments), common share repurchases of $275.2 million, distributions to common shareholders of $171.8 million, distributions to noncontrolling interests of $134.6 million and distributions to preferred shareholders of $20.4 million. Our sources of financing cash flows for the year ended December 31, 2024 primarily consisted of $1.3 billion of borrowings (which included $920.0 million of borrowings under our Revolver, $150.0 million from the issuance of the 2034 Notes (as defined in Note 8 to the consolidated financial statements in Item 8), $125.0 million from the issuance of the September 2031 Notes (as defined in Note 8 to the consolidated financial statements in Item 8) and $75.0 million from the issuance of the September 2028 Notes (as defined in Note 8 to the consolidated financial statements in Item 8)).

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Our primary uses of financing cash flows for the year ended December 31, 2023 were for principal payments on existing debt of $1.2 billion (which included $1.1 billion of principal repayments, including constructive repayments, under the Revolver, $73.5 million in fixed rate mortgage repayments, $50.2 million of constructive repayments of term loan borrowings within our credit facility, and $3.3 million of scheduled fixed rate mortgage principal amortization payments), common share repurchases of $310.2 million, distributions to common shareholders of $190.9 million, distributions to noncontrolling interests of $141.5 million and distributions to preferred shareholders of $19.0 million. Our sources of financing cash flows for the year ended December 31, 2023 primarily consisted of $1.3 billion of borrowings (which included $898.6 million of borrowings, including constructive borrowings, under our Revolver, $370.0 million from the issuance of July 2028 Notes and October 2023 Senior Unsecured Notes (as defined in Note 8 to the consolidated financial statements in Item 8), and $50.2 million of constructive receipts of term loan borrowings within our credit facility).

Credit Facility and Term Loan Facilities

As of December 31, 2024, our credit facility provided for total borrowings of $1.355 billion, consisting of the following components: (i) a Revolver which provides for a total borrowing commitment up to $950.0 million, whereby we may borrow, repay and re-borrow amounts under the Revolver, (ii) a $275.0 million Term Loan D and (iii) a $130.0 million Term Loan E. The Revolver is set to mature in January 2027; provided that we may elect up to two times to extend the maturity by six months each up to January 2028 by paying an extension fee for each such election of 0.0625% of the total borrowing commitment thereunder at the time of extension and meeting other customary conditions with respect to compliance. The Term Loan D matures in July 2026 and the Term Loan E matures in March 2027. The Revolver, Term Loan D and Term Loan E are not subject to any scheduled reduction or amortization payments prior to maturity. As of December 31, 2024, we had an expansion option under the credit facility, which, if exercised in full, would provide for a total credit facility of $1.900 billion.

As of December 31, 2024, $275.0 million was outstanding under the Term Loan D with an effective interest rate of 3.96% and $130.0 million was outstanding under the Term Loan E with an effective interest rate of 4.89%. As of December 31, 2024, we would have had the capacity to borrow remaining Revolver commitments of $500.0 million while remaining in compliance with the credit facility's financial covenants.

We have a credit agreement with a lender for a term loan facility that matures in December 2028 (the "2028 Term Loan Facility") and is separate from the credit facility in an aggregate amount of $75.0 million. As of December 31, 2024, $75.0 million was outstanding under the 2028 Term Loan Facility with an effective interest rate of 4.62%. We have an expansion option under the 2028 Term Loan Facility, which, if exercised in full, would provide for total borrowings in an aggregate amount up to $125.0 million.

We have a credit agreement with a lender for a term loan facility that matures in April 2029 (the "April 2029 Term Loan Facility") and is separate from the credit facility and 2028 Term Loan Facility in an aggregate amount of $100.0 million. As of December 31, 2024 the entire amount was outstanding under the April 2029 Term Loan Facility with an effective interest rate of 4.27%.

We have a June 2029 Term Loan Facility that matures in June 2029 (the "June 2029 Term Loan Facility") and is separate from the credit facility, 2028 Term Loan Facility, and April 2029 Term Loan Facility in an aggregate amount of $285.0 million. As of December 31, 2024, the June 2029 Term Loan Facility had an effective interest rate of 5.37%. We have an expansion option under the June 2029 Term Loan Facility, which, if exercised in full, would provide for total borrowings in an aggregate amount up to $300.0 million.

For a summary of our financial covenants and additional detail regarding our credit facility, 2028 Term Loan Facility, April 2029 Term Loan Facility and June 2029 Term Loan Facility, please see Note 8 to the consolidated financial statements in Item 8.

2029 and August 2031 Senior Unsecured Notes

On August 30, 2019, our operating partnership issued $100.0 million of 3.98% senior unsecured notes due August 30, 2029 (the "2029 Notes") and $50.0 million of 4.08% senior unsecured notes due August 30, 2031 (the "August 2031 Notes") in a private placement to certain institutional investors.

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August 2030 and August 2032 Senior Unsecured Notes

On October 22, 2020, our operating partnership issued $150.0 million of 2.99% senior unsecured notes due August 5, 2030 (the "August 2030 Notes") and $100.0 million of 3.09% senior unsecured notes due August 5, 2032 (the "August 2032 Notes") in a private placement to certain institutional investors.

May 2026, May 2031 and May 2033Senior Unsecured Notes

On May 26, 2021, our operating partnership issued $55.0 million of 3.10% senior unsecured notes due May 4, 2033 (the "May 2033 Notes"). On July 26, 2021, our operating partnership issued $35.0 million of 2.16% senior unsecured notes due May 4, 2026 (the "May 2026 Notes") and $90.0 million of 3.00% senior unsecured notes due May 4, 2031 (the "May 2031 Notes").

November 2030, November 2031, November 2033 and 2036Senior Unsecured Notes

On December 14, 2021, our operating partnership issued $75.0 million of 2.72% senior unsecured notes due November 30, 2030 (the "November 2030 Notes"), $175.0 million of 2.81% senior unsecured notes due November 30, 2031 (the "November 2031 Notes") and $75.0 million of 3.06% senior unsecured notes due November 30, 2036 (the "2036 Notes"). On January 28, 2022, our operating partnership issued $125.0 million of 2.96% senior unsecured notes due November 30, 2033 (the "November 2033 Notes").

November 2032 Senior Unsecured Notes

On September 28, 2022, the operating partnership issued $200.0 million of 5.06% senior unsecured notes due November 16, 2032 (the "November 2032 Notes").

July 2028 Senior Unsecured Notes

On April 27, 2023, our operating partnership issued $120.0 million of 5.61% senior unsecured notes due July 5, 2028 (the "July 2028 Notes") in a private placement to certain institutional investors. The July 2028 Notes have an effective interest rate of 5.75% after taking into account the effect of interest rate swaps.

October 2026, October 2028, October 2030 and October 2033Senior Unsecured Notes

On October 5, 2023, our operating partnership issued $65.0 million of 6.46% senior unsecured notes due October 5, 2026 (the "October 2026 Notes"), $100.0 million of 6.55% senior unsecured notes due October 5, 2028 (the "October 2028 Notes"), $35.0 million of 6.66% senior unsecured notes due October 5, 2030 (the "October 2030 Notes") and $50.0 million of 6.73% senior unsecured notes due October 5, 2033 (the "October 2033 Notes") in a private placement to certain institutional investors.

September 2028, September 2031 and 2034 Senior Unsecured Notes

On September 5, 2024, our operating partnership issued $75.0 million of 5.40% senior unsecured notes due September 5, 2028 (the "September 2028 Notes"), $125.0 million of 5.55% senior unsecured notes due September 5, 2031 (the "September 2031 Notes"), and $150.0 million of 5.74% senior unsecured notes due September 5, 2034 ("September 2034 Notes") in a private placement to certain institutional investors.

Sources of Liquidity and Capital Resources

As of December 31, 2024, we had $50.4 million in cash and cash equivalents, compared to $65.0 million as of December 31, 2023. Our cash flows from operations result primarily from the ownership and management of self storage facilities as described in Part I, Item 1, "Business".

Our material cash requirements from contractual and other obligations primarily relate to our debt obligations. Expected timing of those payments are as follows. The information in this section should be read in conjunction with Note 8 and other information included in the accompanying consolidated financial statements included in Item 8.

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(dollars in thousands) Next 12 Months Beyond 12 Months Total

(1) Under the credit facility, the Company has an expansion option which if exercised in full, would provide an additional $545 million of borrowing capacity.

We anticipate our current cash balances, cash flows from operations and available sources of liquidity will be sufficient to fund operations and meet our short-term and long-term cash requirements, including our scheduled debt repayments, payments for contractual obligations, acquisitions, capital expenditures, working capital needs, dividends, and other prudent uses of our capital, as needed. However, we will continue to assess our liquidity needs. In the event of certain market conditions, we may require additional liquidity, which would require us to evaluate available alternatives and take appropriate actions.

Equity Transactions

Issuance and Repurchase of Common Shares

On December 1, 2023, we approved a new share repurchase program authorizing, but not obligating, the repurchase of up to $275.0 million of the Company's common shares from time to time. During the year ended December 31, 2024, we repurchased 7,400,322 common shares for approximately $275.2 million (inclusive of commissions and fees). On November 14, 2024, the Company approved a new share repurchase program authorizing, but not obligating, the repurchase of up to $350.0 million of the Company's common shares from time to time.

During the year ended December 31, 2024, after receiving notices of redemption from certain OP unitholders, we elected to issue 1,454,837 common shares to such holders in exchange for 1,454,837 OP units in satisfaction of the operating partnership's redemption obligations.

Issuance and Redemption of OP Equity

As discussed in Note 3 to the consolidated financial statements in Item 8, during the year ended December 31, 2024, we issued (i) 14,376,264 OP units upon the conversion of 7,772,693 subordinated performance units due to the internalization of the PRO structure, (ii) 1,548,866 OP units in connection with the purchase of the PROs' intangible assets, (iii) 43,556 OP units upon the conversion of 23,690 subordinated performance units, and (iv) 92,174 OP units upon the conversion of an equivalent number of LTIP units. In addition, we redeemed 28,017 OP units, 194,888 subordinated performance units for cash and 9,742 Series A-1 preferred units for an equivalent number of Series A Preferred Shares.

During the year ended December 31, 2024, we issued 3,608,523 DownREIT OP units upon the conversion of 4,133,474 DownREIT subordinated performance units due to the internalization of the PRO structure and 40,200 DownREIT OP units that were issued in exchange for OP units.

Dividends and Distributions

During the year ended December 31, 2024, the Company paid $171.8 million of distributions to common shareholders, $20.4 million of distributions to preferred shareholders and distributed $134.6 million to noncontrolling interests.

On February 13, 2025, our board of trustees declared a cash dividend and distribution, respectively, of $0.57 per common share and OP unit to shareholders and OP unitholders of record as of March 14, 2025. On February 13, 2025, our board of trustees also declared cash distributions of $0.375 per Series A Preferred Share, Series B Preferred Share and Series A-1 preferred unit to shareholders and unitholders of record as of March 14, 2025.

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Segment

We manage our business as one reportable segment consisting of owning and managing self storage properties located in the United States. Although we operate in several markets, these operations have been aggregated into one reportable segment based on the similar economic characteristics among all markets (see Note 15 to the consolidated financial statements in Item 8 for more information).

Seasonality

The self storage business is subject to minor seasonal fluctuations. A greater portion of revenues and profits are realized from May through September. Historically, our highest level of occupancy has typically been in July, while our lowest level of occupancy has typically been in February. Results for any quarter may not be indicative of the results that may be achieved for the full fiscal year.

ITEM 7A. Quantitative and Qualitative Disclosures About Market Risk

Market risk refers to the risk of loss from adverse changes in market prices and interest rates. Our future income, cash flows, and fair values of financial instruments are dependent upon prevailing market interest rates. The primary market risk to which we believe we are exposed is interest rate risk. Interest rate risk is highly sensitive to many factors, including governmental monetary and tax policies, domestic and international economic and political considerations, and other factors beyond our control. We use interest rate swaps to moderate our exposure to interest rate risk by effectively converting the interest on variable rate debt to a fixed rate. We make limited use of other derivative financial instruments and we do not use them for trading or other speculative purposes. Further, we may reduce our debt subject to variable rates to decrease our exposure to interest rate risk.

As of December 31, 2024, we had $223.3 million of debt subject to variable interest rates (excluding variable-rate debt subject to interest rate swaps). If our reference rates (SOFR) were to increase or decrease by 100 basis points, the increase or decrease in interest expense on the variable-rate debt (excluding variable-rate debt subject to interest rate swaps) would decrease or increase future earnings and cash flows by approximately $2.2 million annually.

Interest rate risk amounts were determined by considering the impact of hypothetical interest rates on our financial instruments. These analyses do not consider the effect of any change in overall economic activity that could occur. Further, in the event of a change of that magnitude, we may take actions to further mitigate our exposure to the change. However, due to the uncertainty of the specific actions that would be taken and their possible effects, these analyses assume no changes in our financial structure.

Item 8. Financial Statements and Supplementary Data

The independent registered public accounting firm's reports, consolidated financial statements and schedule listed in the accompanying index are filed as part of this report and incorporated herein by this reference. See "Index to Financial Statements" on page F-1 of this Annual Report on Form 10-K.

Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures

Disclosure Controls and Procedures

A review and evaluation was performed by our management, including our Chief Executive Officer (the "CEO") and Chief Financial Officer (the "CFO"), of the effectiveness of the design and operation of our disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act), as of the end of the period covered by this Annual Report on Form 10-K. Based on that review and evaluation, the CEO and CFO have concluded that our current disclosure controls and procedures, as designed and implemented, were effective.

Notwithstanding the foregoing, a control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that it will detect or uncover failures within the Company to disclose material information otherwise required to be set forth in our periodic reports.

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Management's Annual Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) promulgated under the Exchange Act as a process designed by, or under the supervision of, our principal executive and principal financial officers and effected by our board of trustees, audit committee, management and other personnel to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with U.S. GAAP and includes those policies and procedures that:

•pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the Company;

•provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S. GAAP, and that our receipts and expenditures are being made only in accordance with authorizations of our management and trustees; and

•provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Projections of any evaluation of effectiveness to future periods are subject to the risks that controls may become inadequate because of changes in conditions or that the degree of compliance with the policies or procedures may deteriorate.

Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2024. In making this assessment, our management used criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control-Integrated Framework (2013 Framework).

Based on this assessment, our management believes that, as of December 31, 2024, our internal control over financial reporting was effective based on those criteria.

The Company’s independent registered public accounting firm has issued an attestation report on the Company’s internal control over financial reporting.

Changes in Internal Control Over Financial Reporting

There have been no changes in our internal control over financial reporting that occurred during the quarter ended December 31, 2024 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Item 9B. Other Information

Rule 10b5-1 Trading Plans

During the quarter ended December 31, 2024, no trustee or officer of the Company adopted or terminated any Rule 10b5-1 trading arrangements or non-Rule 10b5-1 trading arrangements (in each case, as defined in Item 408(a) of Regulation S-K).

PART III

Item 10. Directors, Executive Officers and Corporate Governance

Incorporation by reference

The information regarding our trustees, executive officers and certain other matters required by Item 401 of Regulation S-K is incorporated herein by reference to our definitive proxy statement relating to our annual meeting of shareholders (the "Proxy Statement"), to be filed with the SEC within 120 days after December 31, 2024.

The information regarding compliance with Section 16(a) of the Exchange Act required by Item 405 of Regulation S-K is incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

The information regarding our Code of Business Conduct and Ethics required by Item 406 of Regulation S-K is incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

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The information regarding certain matters pertaining to our corporate governance required by Item 407(c)(3), (d)(4) and (d)(5) of Regulation S-K is incorporated by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

The information regarding our insider trading policies and procedures required by Item 408(b) of Regulation S-K is incorporated herein by reference to the Proxy Statement, to be filed with the SEC within 120 days after December 31, 2024.

Item 11. Executive Compensation

The information regarding executive compensation and other compensation related matters required by Items 402 and 407(e)(4) and (e)(5) of Regulation S-K is incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

The tables on equity compensation plan information and beneficial ownership of the Company required by Items 201(d) and 403 of Regulation S-K are incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

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

The information regarding transactions with related persons, promoters and certain control persons and trustee independence required by Items 404 and 407(a) of Regulation S-K is incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

Item 14. Principal Accounting Fees and Services

The information concerning principal accounting fees and services and the Audit Committee's pre-approval policies and procedures required by Item 14 is incorporated herein by reference to the Proxy Statement to be filed with the SEC within 120 days after December 31, 2024.

PART IV

Item 15. Exhibits, Financial Statement Schedules

(a)(1) The financial statements listed in the Index to Financial Statements on Page F-1 of this report are filed as part of this report and incorporated herein by reference.

(a)(2) The financial statement schedule listed in the Index to Financial Statements on Page F-1 of this report is filed as part of this report and incorporated herein by reference.

(a)(3) The Exhibit Index is incorporated herein by reference.

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INDEX TO EXHIBITS

Exhibit Number Exhibit Description

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19.1* Statement of Corporate Policy Regarding Equity Transactions

21.1* List of subsidiaries of National Storage Affiliates Trust

23.1* Consent of KPMG LLP for National Storage Affiliates Trust

24.1* Power of Attorney (included on signature page)

101.SCH* Inline XBRL Taxonomy Extension Schema

101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase

101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase

101.LAB* Inline XBRL Taxonomy Extension Label Linkbase

101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase

* Filed herewith.

Item 16. Form 10-K Summary

None.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

National Storage Affiliates Trust

By: /s/ DAVID G. CRAMER

David G. Cramer

president and chief executive officer

(principal executive officer)

Date: February 27, 2025

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints David G. Cramer, Brandon S. Togashi and John J. Esbenshade and each of them, with full power to act without the other, such person's true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign this Form 10-K and any and all amendments thereto, and to file the same, with exhibits and schedules thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing necessary or desirable to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

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Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned and in the capacities and on the dates indicated.

Signature Title Date

National Storage Affiliates Trust

David G. Cramer (principal executive officer)

Brandon S. Togashi (principal financial officer)

John J. Esbenshade (principal accounting officer)

Tamara D. Fischer

Arlen D. Nordhagen

/s/ WARREN W. ALLAN trustee February 27, 2025

Warren W. Allan

/s/ LISA R. COHN trustee February 27, 2025

Lisa R. Cohn

/s/ PAUL W. HYLBERT, JR. trustee February 27, 2025

Paul W. Hylbert, Jr.

/s/ CHAD L. MEISINGER trustee February 27, 2025

Chad L. Meisinger

/s/ STEVEN G. OSGOOD trustee February 27, 2025

Steven G. Osgood

/s/ DOMINIC M. PALAZZO trustee February 27, 2025

Dominic M. Palazzo

/s/ MICHAEL J. SCHALL trustee February 27, 2025

Michael J. Schall

/s/ REBECCA L. STEINFORT trustee February 27, 2025

Rebecca L. Steinfort

/s/ CHARLES F. WU trustee February 27, 2025

Charles F. Wu

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NATIONAL STORAGE AFFILIATES TRUST

INDEX TO FINANCIAL STATEMENTS

Page

Financial Statements:

Reports of Independent Registered Public Accounting Firm F-2

Consolidated Balance Sheets as of December 31, 2024 and 2023 F-5

Notes to the Consolidated Financial Statements F-13

Financial Statement Schedule:

Schedule III - Real Estate and Accumulated Depreciation F-48

F-1

Table of Contents

Report of Independent Registered Public Accounting Firm

To the Shareholders and Board of Trustees

National Storage Affiliates Trust:

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheets of National Storage Affiliates Trust and subsidiaries (the Company) as of December 31, 2024 and 2023, the related consolidated statements of operations, comprehensive income (loss), changes in equity, and cash flows for each of the years in the three‐year period ended December 31, 2024, and the related notes and financial statementSchedule III – Real Estate and Accumulated Depreciation (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the years in the three‐year period ended December 31, 2024, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission, and our report dated February 27, 2025 expressed an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of a critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Expected holding period for self storage properties

As discussed in Note 4 to the consolidated financial statements, the Company had $4,812,496 thousand of self storage properties, net, as of December 31, 2024. The Company evaluates the recoverability of the carrying value of self storage properties whenever events or circumstances indicate that there may be impairment.

We identified the assessment of the Company’s evaluation of the expected holding period for self storage properties as a critical audit matter. Subjective auditor judgment was required to evaluate the reasonableness of management’s expected holding period for self storage properties. Changes in the Company’s judgments regarding the holding period for these assets could have had a significant impact on the determination of their recoverability.

F-2

Table of Contents

The following are the primary procedures we performed to address this critical audit matter. We evaluated the design and tested the operating effectiveness of an internal control in the Company’s impairment process related to management’s expected holding period for self storage properties. We inquired of management and obtained written representations regarding potential property disposal plans. We read minutes of the meetings of the Company’s Board of Trustees to identify and evaluate management’s plans for disposal of any self storage properties. We inquired of the Company’s plans for its self storage properties with those in the organization who are responsible for, and have authority over, potential disposition activities. We compared management’s assessment of self storage properties with potential shortened expected holding period to information obtained from those in the organization responsible for disposition activities. We evaluated the reasonableness of management’s expected holding period for self storage properties by inspecting listings from external sources of real estate properties for sale by the Company.

/s/ KPMG LLP

We have served as the Company’s auditor since 2013.

Denver, Colorado

February 27, 2025

F-3

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Report of Independent Registered Public Accounting Firm

To the Shareholders and Board of Trustees

National Storage Affiliates Trust:

Opinion on Internal Control Over Financial Reporting

We have audited National Storage Affiliates Trust and subsidiaries’ (the Company) internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2024 and 2023, the related consolidated statements of operations, comprehensive income (loss), changes in equity, and cash flows for each of the years in the three-year period ended December 31, 2024, and the related notes and financial statement Schedule III – Real Estate and Accumulated Depreciation (collectively, the consolidated financial statements), and our report dated February 27, 2025 expressed an unqualified opinion on those consolidated financial statements.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management’s Annual Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ KPMG LLP

Denver, Colorado

February 27, 2025

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED BALANCE SHEETS

(dollars in thousands, except per share amounts)

December 31,

ASSETS

Real estate

Investment in unconsolidated real estate ventures 246,193 211,361

Assets held for sale, net — 550,199

LIABILITIES AND EQUITY

Liabilities

Accounts payable and accrued liabilities 98,657 92,766

Interest rate swap liabilities 471 3,450

Commitments and contingencies (Note 12)

Equity

Accumulated other comprehensive income 15,548 21,058

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF OPERATIONS

(in thousands, except per share amounts)

Year Ended December 31,

REVENUE

OPERATING EXPENSES

OTHER (EXPENSE) INCOME

Loss on early extinguishment of debt (323) (758) —

Net income attributable to noncontrolling interests (71,752) (80,319) (80,028)

Earnings per share - basic $ 1.18 $ 1.58 $ 0.99

Earnings per share - diluted $ 1.18 $ 1.48 $ 0.99

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)

(dollars in thousands)

Year Ended December 31,

Other comprehensive income (loss)

Realized loss on derivative contracts — (1,643) —

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

(dollars in thousands, except share amounts)

Accumulated

Additional Distributions Other

Number Amount Number Amount Capital Earnings (Loss) Income Interests Equity

OP equity issued for property acquisitions:

Internalization of PRO, net of offering costs — — — — — — — 3,217 3,217

Equity-based compensation expense — — — — 410 — — 5,848 6,258

Issuance of restricted common shares — — 10,405 — — — — — —

Preferred share dividends — — — — — (13,425) — — (13,425)

Distributions to noncontrolling interests — — — — — — — (140,919) (140,919)

OP equity issued for property acquisitions:

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (CONTINUED)

(dollars in thousands, except share amounts)

Accumulated

Additional Distributions Other

Number Amount Number Amount Capital Earnings (Loss) Income Interests Equity

Issuance of Series A-1 preferred units — — — — — — — 750 750

Equity-based compensation expense — — — — 419 — — 6,260 6,679

Issuance of restricted common shares — — 12,856 — — — — — —

Preferred share dividends — — — — — (19,019) — — (19,019)

Distributions to noncontrolling interests — — — — — — — (141,246) (141,246)

Equity-based compensation expense — — — — 447 — — 7,863 8,310

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (CONTINUED)

(dollars in thousands, except share amounts)

Accumulated

Additional Distributions Other

Number Amount Number Amount Capital Earnings (Loss) Income Interests Equity

Issuance of restricted common shares — — 9,413 — — — — — —

Equity offering costs — — — — (895) — — — (895)

Preferred share dividends — — — — — (20,445) — — (20,445)

Distributions to noncontrolling interests — — — — — — — (134,489) (134,489)

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF CASH FLOWS

(dollars in thousands)

Year Ended December 31,

OPERATING ACTIVITIES

Amortization of debt discount and premium, net (610) (561) (698)

INVESTING ACTIVITIES

Deposits and advances for self storage property and other acquisitions (198) — —

Investment in unconsolidated real estate ventures (74,215) — (55,044)

Expenditures for corporate furniture, equipment and other (1,923) (1,318) (928)

Acquisition of intangible assets from our former PROs (32,741) (16,924) —

FINANCING ACTIVITIES

Redemption of OP equity (9,504) — —

Equity offering costs (699) — (772)

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

CONSOLIDATED STATEMENTS OF CASH FLOWS (CONTINUED)

(dollars in thousands)

Year Ended December 31,

CASH, CASH EQUIVALENTS AND RESTRICTED CASH

Supplemental Cash Flow Information

Supplemental Disclosure of Non-Cash Investing and Financing Activities

Consideration exchanged in investment activity:

Issuance of Series B preferred shares — 113,129 —

Deposits on acquisitions applied to purchase price — — 800

Internalization of PRO structure

Change in accrued capital spending 957 1,260 57

See notes to consolidated financial statements.

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NATIONAL STORAGE AFFILIATES TRUST

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. ORGANIZATION AND NATURE OF OPERATIONS

National Storage Affiliates Trust was organized in the state of Maryland on May 16, 2013 and is a fully integrated, self-administered and self-managed real estate investment trust focused on the self storage sector. As used herein, "NSA," the "Company," "we," "our," and "us" refers to National Storage Affiliates Trust and its consolidated subsidiaries, except where the context indicates otherwise. The Company has elected and believes that it has qualified to be taxed as a real estate investment trust for U.S. federal income tax purposes ("REIT") commencing with its taxable year ended December 31, 2015.

Through its controlling interest as the sole general partner of NSA OP, LP (its "operating partnership"), a Delaware limited partnership formed on February 13, 2013, the Company is focused on the ownership, operation, and acquisition of self storage properties predominantly located within the top 100 MSAs in the United States. Pursuant to the Agreement of Limited Partnership (as amended, the "LP Agreement") of its operating partnership, the Company's operating partnership is authorized to issue preferred units, Class A Units ("OP units") and Long-Term Incentive Plan Units ("LTIP units"). The Company also owns certain of its self storage properties through other consolidated limited partnership subsidiaries of its operating partnership, which the Company refers to as "DownREIT partnerships." The DownREIT partnerships issue equity ownership interests that are intended to be economically equivalent to the Company's OP units ("DownREIT OP units").

The Company owned, managed and controlled 815 of its consolidated self storage properties in 38 states and Puerto Rico with approximately 52.2 million rentable square feet in approximately 409,000 storage units as of December 31, 2024. These properties are managed with local operational focus and expertise.

As of December 31, 2024, the Company also managed through its property management platform an additional portfolio of 259 properties owned by the Company's unconsolidated real estate ventures. These properties contain approximately 18.0 million rentable square feet, configured in approximately 143,000 storage units and located across 24 states. The Company owns a 25% equity interest in each of its unconsolidated real estate ventures.

As of December 31, 2024, in total, the Company operated and held ownership interests in 1,074 self storage properties located across 42 states and Puerto Rico with approximately 70.2 million rentable square feet in approximately 552,000 storage units.

Information with respect to the square feet and number of storage units in each of the notes is unaudited.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying consolidated financial statements are presented on the accrual basis of accounting in accordance with U.S. generally accepted accounting principles ("GAAP").

Principles of Consolidation

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

When the Company obtains an economic interest in an entity, the Company evaluates the entity to determine if the entity is deemed a variable interest entity ("VIE"), and if the Company is 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, the Company considers 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. The Company consolidates all entities that are VIEs and of which the Company is deemed to be the primary beneficiary. The Company has determined that its operating partnership is a VIE. The sole significant asset of National Storage Affiliates Trust is its investment in its operating partnership, and consequently, substantially all of the Company's assets and liabilities represent those assets and liabilities of its operating partnership.

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As of December 31, 2024, the Company's operating partnership was the primary beneficiary of, and therefore consolidated, 22 DownREIT partnerships that are considered VIEs, which owned 49 self storage properties. The net book value of the real estate owned by these VIEs was $407.1 million and $418.9 million as of December 31, 2024 and December 31, 2023, respectively. For certain DownREIT partnerships which are subject to fixed rate mortgages payable, the carrying value of such fixed rate mortgages payable held by these VIEs was $172.9 million and $188.7 million as of December 31, 2024 and December 31, 2023, respectively. The creditors of the consolidated VIEs do not have recourse to the Company's general credit.

Noncontrolling Interests

All of the limited partner equity interests ("OP equity") in its operating partnership not held by the Company are reflected as noncontrolling interests. Noncontrolling interests also include ownership interests in DownREIT partnerships held by entities other than the Company's operating partnership. In the consolidated statements of operations, the Company allocates net income (loss) attributable to noncontrolling interests to arrive at net income (loss) attributable to National Storage Affiliates Trust.

For transactions that result in changes to the Company's ownership interest in its operating partnership, the carrying amount of noncontrolling interests is adjusted to reflect such changes. The difference between the fair value of the consideration received or paid and the amount by which the noncontrolling interests is adjusted is reflected as an adjustment to additional paid-in capital on the consolidated balance sheets.

Self Storage Properties

Self storage properties are carried at historical cost less accumulated depreciation and any impairment losses. Major replacements and betterments, which improve or extend the life of an asset, are capitalized. Expenditures for ordinary repairs and maintenance are expensed as incurred and are included in property operating expenses. Estimated depreciable lives of self storage properties are determined by considering the age and other indicators about the condition of the assets at the respective dates of acquisition, resulting in a range of estimated useful lives for assets within each category. All self storage property assets are depreciated using the straight-line method. Buildings and improvements are depreciated over estimated useful lives primarily between seven and 40 years; furniture and equipment are depreciated over estimated useful lives primarily between three and 10 years.

When a self storage property is acquired, the purchase price of the acquired self storage property is allocated to land, buildings and improvements, furniture and equipment, customer in-place leases, assumed real estate leasehold interests, and other assets acquired and liabilities assumed, based on the estimated fair value of each component. When a portfolio of self storage properties is acquired, the purchase price is allocated to the individual self storage properties based on the fair value determined using an income approach with appropriate risk-adjusted capitalization rates, which take into account the relative size, age and location of the individual self storage properties.

Cash and Cash Equivalents

The Company considers all highly-liquid investments purchased with original maturities of three months or less to be cash equivalents. From time to time, the Company maintains cash balances in financial institutions in excess of federally insured limits. The Company has never experienced a loss that resulted from exceeding federally insured limits.

Restricted Cash

The Company's restricted cash consists of escrowed funds deposited with financial institutions resulting from property sales for which we elected to purchase replacement property in accordance with Section 1031 of the Code, and for real estate taxes, insurance and other reserves for capital improvements in accordance with the Company's loan agreements.

Customer In-place Leases

In allocating the purchase price for a self storage property acquisition, the Company determines whether the acquisition includes intangible assets. The Company allocates a portion of the purchase price to an intangible asset attributed to the value of customer in-place leases. This intangible asset is amortized to expense using the straight-line method over 12 months, the estimated average rental period for the leases. Substantially all of the leases in place at acquired properties are at market rates, as the leases are month-to-month contracts.

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Impairment of Long-Lived Assets

The Company evaluates long-lived assets for impairment when events and circumstances indicate that there may be impairment. When events or changes in circumstances indicate that the Company's long-lived assets may not be recoverable, the carrying value of these long-lived assets is compared to the undiscounted future net operating cash flows, plus a terminal value attributable to the assets. If an asset's carrying value is not considered recoverable, an impairment loss is recorded to the extent the net carrying value of the asset exceeds the fair value. For the periods presented, no assets were determined to be impaired under this policy.

Long Lived Assets Held for Sale

The Company considers long-lived assets to be “held for sale” upon satisfaction of the following criteria: (a) management commits to a plan to sell an asset (or group of assets), (b) the asset is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such assets, (c) an active program to locate a buyer and other actions required to complete the plan to sell the asset have been initiated, (d) the sale of the asset is probable and transfer of the asset is expected to be completed within one year, (e) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value and (f) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn.

Typically these criteria are all met when the relevant asset is under contract, significant non-refundable deposits have been made by the potential buyer, the assets are immediately available for transfer, and there are no contingencies related to the sale that may prevent the transaction from closing. However, each potential transaction is evaluated based on its separate facts and circumstances. Assets classified as held for sale are reported at the lesser of carrying value or fair value less estimated costs to sell and are not depreciated. As of December 31, 2024, the Company had no self storage properties classified as held for sale. As of December 31, 2023, the Company had $550.2 million of self storage properties classified as held for sale, consisting of 39 self storage properties to be sold to an unaffiliated third party in 2024 and 56 self storage properties that were contributed to the 2024 Joint Venture (as defined in Note 5) in February 2024. The Company measured the self storage properties' fair value based on the contracted sale price and determined there was no impairment of these properties.

Costs of Raising Capital

Commissions, legal fees and other costs that are directly associated with equity offerings are capitalized as deferred offering costs, pending a determination of the success of the offering. Deferred offering costs related to successful offerings are charged to additional paid-in capital within equity in the period it is determined that the offering was successful.

Debt issuance costs are amortized over the estimated life of the related debt using the straight-line method, which approximates the effective interest rate method. Amortization of debt issuance costs is included in interest expense in the accompanying consolidated statements of operations.

Revenue Recognition

Rental revenue

Rental revenue consists of space rentals and related fees. Management has determined that all of the Company's leases are operating leases. Substantially all leases may be terminated on a month-to-month basis and rental income is recognized ratably over the lease term using the straight-line method. Rents received in advance are deferred and recognized on a straight-line basis over the related lease term associated with the prepayment. Promotional discounts and other incentives are recognized as a reduction to rental income over the applicable lease term.

Other property-related revenue

Other property-related revenue primarily consists of ancillary revenues such as tenant insurance and/or tenant warranty protection-related access fees and sales of storage supplies which are recognized in the period earned.

The Company has tenant insurance and/or tenant warranty protection plan-related arrangements with insurance companies and the Company’s tenants. During the years ended December 31, 2024, 2023 and 2022, the Company recognized $22.9 million, $24.1 million and $19.8 million, respectively, of tenant insurance and tenant warranty protection plan revenues.

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The Company sells boxes, packing supplies, locks and other retail merchandise at its properties. During the years ended December 31, 2024, 2023 and 2022, the Company recognized retail sales of $1.9 million, $2.3 million and $2.6 million, respectively.

Management fees and other revenue

Management fees and other revenue consist of property management fees, platform fees, call center fees, acquisition fees, amounts related to the facilitation of tenant warranty protection or tenant insurance programs for certain stores in the Company's consolidated portfolio and unconsolidated real estate ventures, access fees associated with tenant insurance-related arrangements, and profit distributions from the Company's interest in a reinsurance company.

With respect to the 2016 Joint Venture, the 2018 Joint Venture, the 2023 Joint Venture and the 2024 Joint Venture (each as defined in Note 5), the Company provides supervisory and administrative property management services, centralized call center services, and technology platform and revenue management services to the properties in the unconsolidated real estate ventures. The property management fees for the 2016 Joint Venture, 2018 Joint Venture and 2023 Joint Venture are equal to 6% of monthly gross revenues and net sales revenues from the assets of the unconsolidated real estate ventures, and the platform fees are equal to $1,250 per month per unconsolidated real estate venture property. The property management fees for the 2024 Joint Venture are equal to 4% of monthly gross revenues and net sales revenues from the assets of the unconsolidated real estate venture. With respect to the 2016 Joint Venture, the 2023 Joint Venture and 2024 Joint Venture, the call center fee is equal to 1% of each of monthly gross revenues and net sales revenues. During the years ended December 31, 2024, 2023 and 2022, the Company recognized property management fees, call center fees and platform fees of $18.3 million, $16.8 million and $16.5 million, respectively.

The Company also earns acquisition fees for properties acquired by the 2016 Joint Venture, the 2018 Joint Venture, 2023 Joint Venture and the 2024 Joint Venture. These fees are based on a percentage of the gross capitalization of the acquired assets determined by the members of the 2016 Joint Venture, the 2018 Joint Venture, the 2023 Joint Venture and the 2024 Joint Venture, and are generally earned when the unconsolidated real estate ventures obtain title and control of an acquired property. During the years ended December 31, 2024, 2023 and 2022, the Company recognized acquisition fees of $0.6 million, $0 and $1.2 million, respectively.

The Company provides or makes available tenant insurance or tenant warranty protection programs for tenants at its properties. For certain of the properties in the Company’s consolidated portfolio and unconsolidated real estate ventures, the Company provides such tenant insurance through the Company’s wholly-owned captive insurance company and a separate reinsurance company in which the Company has a partial ownership interest. With respect to properties in the Company’s unconsolidated real estate ventures, the Company receives 50% of all proceeds from tenant insurance and tenant warranty protection programs at each unconsolidated real estate venture property in exchange for facilitating the programs at those properties. During the years ended December 31, 2024, 2023 and 2022, the Company recognized $22.8 million, $17.2 million and $9.5 million, respectively, of revenue related to these activities.

Advertising Costs

The Company incurs advertising costs primarily attributable to internet, directory and other advertising. Advertising costs are included in property operating expenses in the accompanying consolidated statements of operations. These costs are expensed in the period in which the cost is incurred. The Company incurred advertising costs of $15.0 million, $15.3 million and $10.0 million for the years ended December 31, 2024, 2023 and 2022, respectively.

Acquisition Costs

The Company incurs title, legal and consulting fees, and other costs associated with the completion of acquisitions. The Company's self storage property acquisitions are accounted for as asset acquisitions, and accordingly, acquisition costs directly related to the self storage property acquisitions were capitalized as part of the basis of the acquired properties. Indirect acquisition costs remain included in acquisition costs in the accompanying consolidated statements of operations in the period in which they were incurred.

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Income Taxes

The Company has elected and believes it has qualified to be taxed as a REIT under sections 856 through 860 of the U.S. Internal Revenue Code (the "Code") commencing with the taxable year ended December 31, 2015. To qualify as a REIT, among other things, the Company is required to distribute at least 90% of its REIT taxable income to its shareholders and meet certain tests regarding the nature of its income and assets. As a REIT, the Company is not subject to federal income tax on the earnings distributed currently to its shareholders that it derives from its REIT qualifying activities. If the Company fails to qualify as a REIT in any taxable year, and is unable to avail itself of certain provisions set forth in the Code, all of the Company's taxable income would be subject to federal and state income taxes at regular corporate rates.

The Company will not be required to make distributions with respect to income derived from the activities conducted through subsidiaries that the Company elects to treat as taxable REIT subsidiaries ("TRS") for federal income tax purposes. Certain activities that the Company undertakes must be conducted by a TRS, such as performing non-customary services for its customers, facilitating sales of tenant insurance and holding assets that the Company is not permitted to hold directly. A TRS is subject to federal and state income taxes.

On June 25, 2014, the Company formed NSA TRS, LLC ("NSA TRS"), a Delaware limited liability company. The Company has elected to treat NSA TRS as a TRS, and consequently, NSA TRS is subject to U.S. federal and state corporate income taxes. Deferred tax assets and liabilities are recognized to the extent of any differences between the financial reporting and tax bases of assets and liabilities. No material deferred tax assets and liabilities were recorded as of December 31, 2024 and 2023.

The Company did not have any unrecognized tax benefits related to uncertain tax positions as of December 31, 2024 and 2023. Future amounts of accrued interest and penalties, if any, related to uncertain tax positions will be recorded as a component of income tax expense. The Company does not expect that the amount of unrecognized tax benefits will change significantly in the next 12 months.

The Company's material taxing jurisdiction is the U.S. federal jurisdiction; the 2021 tax year is the earliest period that remains open to examination by these taxing jurisdictions.

Earnings per Share

Basic earnings per share is calculated based on the weighted average number of the Company's common shares of beneficial interest, $0.01 par value per share ("common shares"), outstanding during the period. Diluted earnings per share is calculated by further adjusting for the dilutive impact using the treasury stock method for any share options and unvested share equivalents outstanding during the period and the if-converted method for any convertible securities outstanding during the period.

Equity-Based Awards

The measurement and recognition of compensation cost for all equity-based awards granted to officers, trustees, employees and consultants is based on estimated fair values. Compensation cost is recognized on a straight-line basis over the requisite service periods of each award with non-graded vesting. For awards granted which contain a graded vesting schedule and the only condition for vesting is a service condition, compensation cost is recognized as an expense on a straight-line basis over the requisite service period as if the award was, in substance, a single award. For awards granted for which vesting is subject to a performance condition, compensation cost is recognized over the requisite service period if and when the Company concludes it is probable that the performance condition will be achieved.

The estimated fair value of all equity-based awards issued to the Company's former PROs and their affiliates in connection with self storage property acquisitions is included in the cost of the respective acquisitions. The estimated fair value of such awards is measured at the date the self storage properties are acquired, as this date represents satisfaction of the performance condition and coincides with the award vesting.

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Derivative Financial Instruments

The Company carries all derivative financial instruments on the consolidated balance sheet at fair value. Fair value of derivatives is determined by reference to observable prices that are based on inputs not quoted on active markets, but corroborated by market data. The accounting for changes in the fair value of a derivative instrument depends on whether the derivative has been designated and qualifies as part of a hedging relationship. The Company's use of derivative instruments has been limited to interest rate swap and cap agreements. The fair values of derivative instruments are included in other assets and interest rate swap liabilities in the accompanying consolidated balance sheets. For derivative instruments not designated as cash flow hedges, the unrealized gains and losses are included in interest expense in the accompanying consolidated statements of operations. For derivatives designated as cash flow hedges, the effective portion of the changes in the fair value of the derivatives is initially reported in accumulated other comprehensive income (loss) in the Company's consolidated balance sheets and subsequently reclassified into earnings when the hedged transaction affects earnings.

The valuation of interest rate swap and cap agreements is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash payments and the discounted expected variable cash receipts. The variable cash receipts are based on an expectation of future interest rates (forward curves) derived from observable market interest rate forward curves. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk, even though hedge accounting does not apply or the Company elects not to apply hedge accounting.

Fair Value Measurements

When measuring fair value of financial instruments that are required to be recorded or disclosed at fair value, the Company uses a three-tier measurement hierarchy which prioritizes the inputs used to calculate fair value. These tiers include Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

Investments in Unconsolidated Real Estate Ventures

The Company’s investments in its unconsolidated real estate ventures are recorded under the equity method of accounting in the accompanying consolidated financial statements. Under the equity method, the Company’s investments in unconsolidated real estate ventures are stated at cost and adjusted for the Company’s share of net earnings or losses and reduced by distributions. Equity in earnings (losses) is recognized based on the Company’s ownership interest in the earnings (losses) of the unconsolidated real estate ventures. The Company follows the "nature of the distribution approach" for classification of distributions from its unconsolidated real estate ventures in its consolidated statements of cash flows. Under this approach, distributions are reported on the basis of the nature of the activity or activities that generated the distributions as either a return on investment, which are classified as operating cash flows, or a return of investment (e.g., proceeds from the unconsolidated real estate ventures' sale of assets) which are reported as investing cash flows.

Segment Reporting

The Company manages its business as one reportable segment consisting of owning and managing self storage properties located in the United States. Although the Company operates in several markets, these operations have been aggregated into one reportable segment based on the similar economic characteristics among all markets, as discussed further in Note 15.

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