Empire State Realty OP, L.P. ESBA US Equity☆

esrt-20251231

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2025

For the transition period from to

Commission File Number: 001-36106

EMPIRE STATE REALTY OP, L.P.

(Exact name of Registrant as specified in its charter)

111 West 33rd Street, 12th Floor

New York, New York10120

(Address of principal executive offices) (Zip Code)

(212) 687-8700

(Registrant's telephone number, including area code)

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

Title of Each Class Trading Symbol Name of Exchange on Which Registered

Series ES operating partnership units ESBA NYSE Arca, Inc.

Series 60 operating partnership units OGCP NYSE Arca, Inc.

Series 250 operating partnership units FISK NYSE Arca, Inc.

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

None

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

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

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

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

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

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

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

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

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

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

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

As of February 24, 2026, there were 16,479,998 units of the registrants' Series ES operating partnership units outstanding, 4,237,737 units of the Series 60 operating partnership units outstanding, and 2,206,101 units of the Series 250 operating partnership units outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Our sole general partner is Empire State Realty Trust, Inc. Portions of Empire State Realty Trust, Inc.'s Proxy Statement for its 2025 Annual Stockholders' Meeting (which is scheduled to be held on May 14, 2026 in-person) to be filed within 120 days after the end of Empire State Realty Trust, Inc.'s fiscal year are incorporated by reference into Part III of this Annual Report on Form 10-K.

EMPIRE STATE REALTY OP, L.P.

TABLE OF CONTENTS

PAGE

PART I.

1. Business 2

1A. Risk Factors 9

1B. Unresolved Staff Comments 23

1C. Cybersecurity 23

2. Properties 24

3. Legal Proceedings 30

4. Mine Safety Disclosures 30

PART II.

6. [Reserved] 31

7A. Quantitative and Qualitative Disclosure about Market Risk 42

8. Financial Statements and Supplementary Data 42

9A. Controls and Procedures 42

9B. Other Information 45

9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 45

PART III

10. Directors, Executive Officers and Corporate Governance 45

11. Executive Compensation 45

13. Certain Relationships and Related Transactions, and Director Independence 46

14. Principal Accountant Fees and Services 46

PART IV

15. Exhibits, Financial Statements and Schedules 46

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DEFINITIONS

•"annualized rent" represents annualized base rent and current reimbursement for operating expenses and real estate taxes;

•"formation transactions" means a series of transactions pursuant to which we acquired, substantially concurrently with the completion of the initial public offering, through a series of contributions and merger transactions, our commercial portfolio of real estate assets which were held by existing entities, the ownership interests in the certain management entities of our predecessor and one development parcel;

•"enterprise value" means all outstanding shares of Empire State Realty Trust, Inc.'s Class A common stock at the time indicated plus shares of Class A common stock that may be issuable upon the exchange of operating partnership units on a one-for-one basis and shares of Class A common stock issuable upon the conversion of Class B common stock on a one-for-one basis multiplied by the Class A common share price at December 31, 2025, plus private perpetual preferred units plus consolidated debt at December 31, 2025;

•"Malkin Group” means all of the following, as a group: Anthony E. Malkin, Peter L. Malkin and each of their spouses and lineal descendants (including spouses of such descendants), any estates of any of the foregoing, any trusts now or hereafter established for the benefit of any of the foregoing, or any corporation, partnership, limited liability company or other legal entity controlled by Anthony E. Malkin or any permitted successor in such entity for the benefit of any of the foregoing; provided, however that solely with respect to tax protection rights and parties who entered into the contribution agreements with respect to the formation transactions, the Malkin Group shall also include the lineal descendants of Lawrence A. Wien and his spouse (including spouses of such descendants), any estates of the foregoing, any trusts now or hereafter established for the benefit of any of the foregoing, or any corporation, partnership, limited liability company or other legal entity controlled by Anthony E. Malkin for the benefit of the foregoing;

•"our Company," "we," "us" and "our" refer to Empire State Realty OP L.P., a Delaware limited partnership, together with its consolidated subsidiaries;

•"securityholder" means a holder of our Series ES, Series 250, Series 60 and Series PR operating partnership units, including those units held by Empire State Realty Trust, Inc.; and

•"traded OP units" mean our Series ES, Series 250 and Series 60 operating partnership units.

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PART I

ITEM 1. BUSINESS

Overview

Empire State Realty OP, L.P. (the "Operating Partnership") is the entity through which Empire State Realty Trust, Inc. (NYSE: ESRT), is a NYC-focused real estate investment trust ("REIT") that owns and operates a portfolio of well-leased, top of tier, modernized, amenitized, and well-located office, retail, and multifamily assets. ESRT’s flagship Empire State Building, the “World's Most Famous Building,” features its iconic Observatory, ranked the #1 Top Attraction in New York City for the fourth consecutive year in Tripadvisor’s 2025 Travelers’ Choice Awards: Best of the Best Things to Do. The Company is a recognized leader in energy efficiency and indoor environmental quality.

As of December 31, 2025, our portfolio was comprised of approximately 7.9 million rentable square feet of office space, 0.8 million rentable square feet of retail space and 743 residential units, which are located in New York City. Our office portfolio included 10 properties (including three long-term ground leasehold interests), all of which are located in Manhattan. Additionally, we have entitled land in Stamford, Connecticut that can support the development of either office or residential per local zoning.

We were organized as a Delaware limited partnership on November 28, 2011 and commenced operations upon completion of the initial public offering of ESRT’s Class A common stock and related formation transactions on October 7, 2013 (the "Offering"). ESRT's Class A common stock, par value $0.01 per share, is listed on the New York Stock Exchange under the symbol "ESRT." ESRT, as the sole general partner in our Company, has responsibility and discretion in the management and control of our Company, and our limited partners, in such capacity, have no authority to transact business for, or participate in the management activities, of our Company. As of December 31, 2025, ESRT owned approximately 61.4% of our operating partnership units.

Business and Growth Strategies

Our primary business objectives are to maximize cash flow and total returns to our shareholders and to increase the value of our properties through the pursuit of the following strategies:

Lease Space

We believe we benefit from the tenant flight to quality trend. Tenants seek a compelling value proposition from landlords with a strong balance sheet and low leverage that invest in the improvement of their buildings, and we offer a high-qualityexperienceinhigh-qualityassetsatourattractivepricepoint.Ourbuildingsare fully modernized, well-located near mass transit, well-amenitized, and feature industry leadership in energy efficiency and indoor environmental quality, which helps us to draw consistent leasing volumes through cycles. The quality of our commercial portfolio contributed toa strong leasing year in 2025; we leased 1,009,009 square feet of space, including "Early Renewals" which are leases signed over two years prior to the lease expiration, and made meaningful absorption progress with a 90 basis point increase to 89.9% in Manhattan office occupancy, excluding properties under redevelopment, storage and broadcasting. Additionally, we believe our proactive, service-intensive approach to asset and property management helps increase occupancy and rental rates.

We have a brand that we believe tenants associate with a consistently high level of quality of services, healthy buildings, amenities, maintenance, and tenant installations, with high performance design guidelines for energy efficiency and indoor environmental quality, and long-term financial stability. Through our commitment to brokers, we have developed long-term relationships with a focus to attract high quality tenants to our properties. We proactively manage and cultivate our industry relationships and make the most senior members of our management team available to our constituencies. We believe that our consistent, open dialogue with our tenants and brokers enables us to maximize our results. Our focus on performance and long-term perspective allows us to concentrate on the ongoing management of our portfolio, while we concurrently seek opportunities for growth in the future.

We do extensive diligence on our tenants' financial prospects, businesses and business models to determine if we think there is potential to establish long-term relationships in which they will both renew with us and expand over time. Since the initial public offering, we have completed 317 expansions with existing tenants which total 3.2 million square feet within our portfolio.Our comprehensive building management services and our strong commitment to tenant and broker relationships and satisfaction enable us to negotiate attractive leasing deals, which attracts and retains high credit-quality tenants. We proactively

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manage our rent roll, foster strong tenant relationships, maintain continuous communication with our tenants, and are responsive to tenant needs. We believe the success of our long-term tenant relationships improves our operating results over time by reducing tenant turnover and associated costs.

We regularly monitor our properties, perform routine preventive maintenance, and implement capital improvement programs in connection with property redevelopment and life cycle replacement of equipment and systems to protect our investments. We self-manage all of our office and retail properties, and we use a third-party property manager to manage our multifamily properties. We proactively manage our office properties and rent rolls to create efficient, modern, pre-built offices that can be rented through several lease cycles and attract high credit-quality tenants. We manage and control operating expenses at all of our properties. In addition, we have made energy efficiency retrofitting and sustainability a portfolio-wide initiative driven by economic return. We pass on cost savings achieved by such improvements to our tenants through lower utility costs and reduced operating expense escalations.

Sell Tickets to the Empire State Building Observatory

The Empire State Building offers panoramic views of New York and neighboring states from its world-famous 86th and 102nd floor observatories. In December 2019, we completed the Observatory’s comprehensive multi-year reimagination and redevelopment. In 2020, we reprogrammed our Observatory business to operate by reservations only, created a new focus on customer experience and reduction of crowds and lines, with an emphasis on growing revenue per visitor, and matched our hours of operation to the reservations demand to manage expenses. We enhanced health and safety protocols, improved marketing and cross-promotional activities to increase brand awareness, and managed expenses prudently.

Our efforts resulted in strong performance from our Observatory and we experienced improvement in Observatory revenue and operating income from 2021 through 2024. In 2025, revenue and operating income declined as a result of reduced international visitation in excess of increased domestic visitation. We had approximately 2.3 million visitors in 2025, as compared to 2.6 million in 2024 and 2023, 2.2 million in 2022 and 0.8 million in 2021. We grew revenue per visitor in 2025 compared to 2024 and continued our efforts to enhance the guest experience, broaden our marketing reach and drive operational efficiency. Additionally, the Empire State Building Observatory was ranked the #1 Top Attraction in New York City for the fourth consecutive year in Tripadvisor's 2025 Travelers' Choice Awards: Best of the Best Things to Do.

Enhance Shareholder Value

We enhance shareholder value primarily through the execution of our priorities to lease space, sell tickets to the Observatory, manage our balance sheet, and achieve our sustainability goals.

We are diversified and we believe we benefit from New York City’s strength from our office, Observatory, retail, and multifamily exposure in the city. We believe our well-positioned balance sheet, access to capital, and expertise in redevelopment gives us significant flexibility to structure and pursue attractive investment opportunities. Since December 2021, we have completed acquisitions of three multifamily properties in Manhattan, a collection of prime retail assets on North 6th Street in the Williamsburg neighborhood of Brooklyn, NY and 130 Mercer Street, a high-quality mixed-use asset, with office and retail components, in the SoHo submarket of Manhattan. We have also completed the disposition of non-core assets in the New York metropolitan area, including office assets in Stamford, CT, Norwalk, CT, White Plains, NY, and Harrison, NY, and retail assets in Westport, CT. See ITEM 2. Properties for more information.

For the foreseeable future, we intend to focus our acquisition strategy primarily on NYC office, retail and multifamily properties where we can achieve attractive returns on invested capital.

In the current financial environment, we believe our well-positioned balance sheet differentiates us in our efforts to attract brokers and new tenants, who look to partner with financially stable landlords which will invest in their customers and maintain high-quality standards at their assets. Our well-positioned balance sheet has also allowed us to be nimble and recycle and deploy capital.

Achieve Sustainability Goals

We are recognized as a leader in the real estate industry in sustainability, and we focus on energy efficiency, emissions reduction, water use reduction, waste reduction, indoor environmental quality, and healthy buildings. We have pioneered certain practices to achieve emissions reduction and energy efficiency, including those described in our Empire Building Playbook, a free guide that we published in partnership with the New York State Energy Research Development Authority and the Clinton Global Initiative, for existing large commercial and multifamily buildings to follow our lead and develop a technical

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and economic pathway to achieve energy savings with a proven payback. The reduced energy consumption and emissions lower costs for us and our tenants, and we believe creates a competitive advantage for our properties.

Business Segments

Our reportable segments consist of a real estate segment and an Observatory segment. Our real estate segment includes all activities related to the ownership, management, operation, acquisition, repositioning and disposition of our office, retail and multifamily assets principally located in New York City. Our Observatory segment operates the 86th and 102nd floor observatories at the Empire State Building. These segments are managed separately because each business requires different support infrastructure, provides different services and has dissimilar economic characteristics such as investments needed, stream of revenues and marketing strategies. We account for intersegment sales and rent as if the sales or rent were to third parties at current market prices. This intersegment rent is eliminated upon consolidation.

For more information about our segments, refer to “Financial Statements — Note 13 Segment Reporting” in this Annual Report on Form 10-K.

Rental Revenue

We derive revenues primarily from rents, rent escalations, tenant expense reimbursements and other income received from tenants under existing leases at each of our properties. Tenant expense reimbursements consist of payments made by tenants to us under contractual lease obligations to reimburse a portion of the property operating expenses and real estate taxes incurred at each property.

We believe that the average rental rates for in-place leases at our properties are generally below the current market rates, although individual leases at particular properties presently may be leased above, at or below the current market rates within its particular submarket.

Regulation

General

The properties in our portfolio are subject to various laws, ordinances and regulations, including regulations relating to common areas. We believe each of the existing properties has the necessary permits and approvals to operate its business.

Americans with Disabilities Act

Our properties must comply with Title III of the Americans with Disabilities Act, or ("ADA"), to the extent that such properties are “public accommodations” as defined by the ADA. The ADA may require removal of structural barriers to access by persons with disabilities in certain public areas of our properties where such removal is readily achievable. We believe the existing properties are in substantial compliance with the ADA and that we will not be required to make substantial capital expenditures to address the requirements of the ADA. However, noncompliance with the ADA could result in imposition of fines or an award of damages to private litigants. The obligation to make readily achievable accommodations is an ongoing one, and we will continue to assess our properties and to make alterations as appropriate in this respect.

Environmental Matters

Our properties are subject to various laws, ordinances and regulations, and we may be liable for the costs of remediating environmental contamination. See "Risk Factors — We may incur significant costs to comply with environmental laws, and environmental contamination may impair our ability to lease and/or sell real estate" for more information.

Some of our properties are adjacent to or near other properties which are used for industrial or commercial purposes or have contained or currently contain underground storage tanks used to store petroleum products or other hazardous or toxic substances. Releases from these properties could impact our properties. In addition, some of our properties have previously been used by former owners or tenants for commercial or industrial activities, e.g., gas stations and dry cleaners, and a portion of the Metro Tower site, the undeveloped parcel we own adjacent to our recently sold Metro Center asset, is currently used for automobile parking and was formerly leased to a fueling facility that may release petroleum products or other hazardous or toxic substances at such properties or to surrounding properties. While certain properties contain or contained uses that could have or have impacted our properties, we are not aware of any liabilities related to environmental contamination that we believe will have a material adverse effect on our operations.

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In addition, we may become subject to new compliance requirements and/or new costs or taxes associated with natural resource or energy usage and related emissions (such as a carbon tax), which could increase our operating costs. We do not believe we have any instances of material non-compliance with environmental or health and safety laws or regulations at our properties, and we believe that we and/or our tenants have all material permits and approvals necessary under current laws and regulations to operate our properties. See "Risk Factors — We may incur significant costs to comply with environmental laws, for example New York City’s Local Law 97" for more information.

As the owner or operator of real property, we may also incur liability based on various building conditions. See "Risk Factors — We may incur significant costs to comply with environmental laws, and environmental contamination may impair our ability to lease and/or sell real estate" for more information.

Further, our properties may contain or develop harmful mold or suffer from other indoor air or water quality issues, which could lead to liability for adverse health effects or property damage or costs for remediation. We do not believe we have any material liabilities related to building conditions, including any instances of material non-compliance with asbestos requirements or any material liabilities related to asbestos. See "Risk Factors — We may incur significant costs to comply with environmental laws, and environmental contamination may impair our ability to lease and/or sell real estate" for more information.

Affordable Housing

Certain units in our multifamily properties are designated for lower income households and are therefore subject to supervision and regulation by state and federal governmental authorities which regulate affordable housing rental activities. See "Risk Factors — Government housing regulations may limit opportunities at the multifamily properties in which we invest, and failure to comply with resident qualification requirements or to extend such programs upon expiration may result in financial penalties or loss of benefits" for more information.

Insurance

We maintain additional property, business interruption and terrorism coverage for the Empire State Building through ESRT Captive Insurance Company L.L.C., our wholly owned captive insurance subsidiary. Through a combination of commercial insurance, our captive program and participation in the federal terrorism insurance program (as amended, currently extended through December 31, 2027), we maintain aggregate terrorism coverage of up to $2.0 billion for the Empire State Building, including coverage for certain nuclear, biological, chemical and radiological exposures. The federal program operates as a backstop for certified acts of terrorism, subject to applicable deductibles and co-insurance.

The captive maintains reinsurance with third-party insurers; reinsurance does not relieve the captive of its primary obligations, and reinsurer non-performance could result in losses to us. As long as we own the captive, we are responsible for its liquidity and capital resources, and its accounts are included in our consolidated financial statements.

Our policies include substantial self-insurance components and significant deductibles and co-payments for certain events. We do not carry insurance for certain losses (including losses caused by war), and business interruption insurance for pandemic-level or other public health events may not be available on commercially acceptable terms. We may modify or discontinue certain coverage if, in our judgment, the cost of coverage exceeds the value of the coverage relative to the risk of loss.

Competition

The leasing of real estate is highly competitive in New York City where we operate. We compete with numerous acquirers, developers, owners and operators of commercial real estate, many of which own or may seek to acquire or develop properties similar to ours in the same markets in which our properties are located. The principal means of competition are rent charged, location, amenities and services provided, and the nature and condition of the facility to be leased. In addition, we face competition from other real estate companies, including other REITs, private real estate funds, domestic and foreign financial institutions, life insurance companies, pension trusts, partnerships, individual investors and others, that may have greater financial resources or access to capital than we do or that are willing to acquire properties in transactions which are more highly leveraged or are less attractive from a financial viewpoint than we are willing to pursue. In addition, competition from new and existing observatories and/or broadcasting operations may have a negative impact on revenues from our Observatory operations and/or broadcasting revenues. Adverse impacts on domestic and international travel and changes in foreign currency exchange rates may also decrease demand in the future, which could have a material adverse effect on our results of operations, financial condition and ability to make distributions to our securityholders. If our competitors offer space at rental rates below current

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market rates, below the rental rates we currently charge our tenants, in better locations within our markets or in higher quality facilities, we may lose potential tenants and we may be pressured to reduce our rental rates below those we currently charge in order to retain tenants when our tenants’ leases expire.

ESRT's Tax Status as a REIT

ESRT elected to be taxed as a REIT for U.S. federal income tax purposes and intend to continue to qualify as a REIT. To maintain ESRT's qualification, ESRT must satisfy ongoing requirements relating to, among other things, the nature and diversification of its assets, the sources of its income, the ownership of its shares and the amount of its distributions to shareholders. If ESRT qualify as a REIT, it generally will not be subject to U.S. federal corporate income tax on income that it distributes to its shareholders, although it may be subject to tax on certain income, including income from non-qualifying activities conducted through taxable REIT subsidiaries, undistributed taxable income and certain asset dispositions.

ESRT's qualification as a REIT depends upon its ability to meet the various requirements imposed by the Internal Revenue Code, which are highly technical and complex. If ESRT fails to qualify as a REIT in any taxable year and do not qualify for certain available relief provisions, it would be subject to U.S. federal corporate income tax and could be precluded from re-electing REIT status for four taxable years following the year of disqualification. See “Risk Factors — Risks Related to ESRT's REIT Status.”

Inflation

Substantially all of our leases provide for separate real estate tax and operating expense escalations. In addition, many of the leases provide for fixed base rent increases. We believe inflationary increases may be at least partially offset by the contractual rent increases and expense escalations described above. We do not believe inflation has had a material impact on our financial position or results of operations.

Seasonality

Our Observatory business is subject to tourism trends and weather, and therefore does experience some seasonality. For the year ended December 31, 2025, approximately 18% of our annual Observatory revenue was realized in the first quarter, 26% was realized in the second quarter, 28% was realized in the third quarter, and 28% was realized in the fourth quarter. Our multifamily business experiences some seasonality based on general market trends in New York City – the winter months (November through January) are slower in terms of lease activity. We seek to mitigate this by staggering lease terms such that lease expirations are matched with seasonal demand. We do not consider the balance of our business to be subject to material seasonal fluctuations.

Leasing Trend Fluctuations

Due to the relatively small number of leases that are signed in any particular quarter, one or more larger leases may have a disproportionately positive or negative impact on average rent, tenant improvement and leasing commission costs for that period. As a result, we believe it is more appropriate when analyzing trends in average rent and tenant improvement and leasing commission costs to review activity over multiple quarters or years. Tenant improvement costs include expenditures for general improvements occurring concurrently with, but that are not directly related to, the cost of installing a new tenant. Leasing commission costs are similarly subject to significant fluctuations depending upon the length of leases being signed and the mix of tenants from quarter to quarter.

Human Capital Management

As of December 31, 2025, we employed 642 people, of whom approximately 407 are covered by collective bargaining agreements. We generally have and expect to continue to maintain good relations with our employees and workforce, including those employees covered by collective bargaining agreements. We believe that our success is realized through the attraction, retention, development, engagement and empowerment of our highly-valued employees with a wide range of experiences and perspectives, and we endeavor to set our policies and practices accordingly.

We offer what we believe to be generally competitive compensation and benefits. To reward and reinforce participation in the Company’s outcomes, we also make equity grants to employees. We regularly review our compensation and benefits against our peers and the industry to remain competitive.

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We strive to attract, hire and retain candidates who meet our high standards. Our retention strategy is based on the effective training and development of, and focus on the total wellness of, our employees. We believe continuous learning supports productivity, innovation and retention, as well as personal and professional growth for our employees. We invest in employee training, including certain programs which are mandatory for all employees, and other programs which are voluntary and self-directed on platforms provided by the Company. We also regularly assess the performance and potential of our workforce, review our succession plans and create robust developmental action plans to grow our employees and prepare them for internal promotional opportunities. We believe our public recognition demonstrates the strength of our program. We were Great Place to Work-Certified in 2023, 2024 and 2025.

Offices

Our principal executive offices are located at 111 West 33rd Street, 12th floor, New York, New York 10120. We also have additional regional leasing and property management offices in Manhattan. Our current facilities are adequate for our present and future operations, although we may add or eliminate regional offices, depending upon our future operations.

Available Information

ESRT, our sole general partner, has a website address at http://www.esrtreit.com. The information found on, or otherwise accessible through, ESRT's website is not incorporated by reference into, and does not form a part of, this Annual Report on Form 10-K or any other report or document ESRT or we file with or furnish to the SEC and ESRT makes available, free of charge, on or through the SEC Filings section of its website, ESRT's and our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and any amendments to such reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as soon as reasonably practicable after ESRT or we electronically file such material with, or furnish it to, the SEC. ESRT has also posted on its website the Audit Committee Charter, Compensation Committee Charter, Finance Committee Charter, Nominating and Corporate Governance Committee Charter, Corporate Governance Guidelines and Code of Business Conduct and Ethics, which govern its directors, officers and employees. Within the time period required by the SEC, ESRT will post on its website any amendment to its Code of Business Conduct and Ethics and any waiver applicable to its senior financial officers and its executive officers or directors. The SEC maintains an Internet site (http://www.sec.gov) that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC.

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ITEM 1A. RISK FACTORS

You should carefully consider the following risks, together with all other information in this Annual Report on Form 10-K, before you decide to retain or make an investment in our securities. These are not the only risks we face. Additional risks currently unknown or deemed immaterial could have a material adverse effect on us and ESRT's REIT qualification, which could reduce our share price and cause loss of all or part of your investment. Some items below are forward-looking statements. See “Forward-Looking Statements.”

Risks Related to Our Business and Properties

Risks Relating to Portfolio Concentration

Our properties are geographically concentrated in New York, and adverse state or local economic or regulatory developments could have a material adverse effect on our business and financial condition.

Our commercial portfolio is comprised of properties in New York City. As a result, our business is dependent on the New York City economy in general and the market for office, retail and multifamily space in New York City in particular, which exposes us to greater economic and regulatory risks than if we owned a more geographically diverse portfolio. These risks include business layoffs, downsizing, industry slowdowns, and relocations of businesses as well as increases in real estate and other local taxes, and regulatory compliance costs. The current federal tax limits on the deductibility of state and local taxes as well as higher individual tax rate proposals may negatively impact demographic trends in high tax states like New York.

We rely on three properties, in particular the Empire State Building and its Observatory, for a significant portion of our revenue.

For the year ended December 31, 2025, three of our properties together accounted for approximately 55.6% of our portfolio’s rental revenues, with the Empire State Building individually accounting for approximately 32.3%. Our revenue and cash available for distribution would be materially and adversely affected if any of these three properties were materially damaged or a significant number of their tenants experienced financial strain leading to lease default or bankruptcy filing. Additionally, for fiscal years ended December 31, 2025, 2024 and 2023, we derived revenue of approximately $128.3 million, $136.4 million and $129.4 million, respectively, from the Empire State Building’s Observatory operations. Loss of revenue from the Observatory has in the past and may in the future have a material adverse impact on our results of operations and financial condition.

Our five largest tenants represented approximately 17.4% of our total commercial portfolio’s annualized rent as of December 31, 2025.

As of December 31, 2025, our five largest tenants together represented approximately 17.4% of our total commercial portfolio’s annualized rent, with our largest tenant leasing an aggregate of 0.4 million rentable square feet of office space at one of our office properties, representing approximately 4.9% of our total commercial portfolio rentable square feet and approximately 5.5% of our total commercial portfolio annualized rent. Our significant tenants have in the past, and may in the future, experience financial strain leading to lease default or bankruptcy. In such cases, we may not recover our upfront investments in tenant improvement allowances, concessions, and transaction costs like professional fees and commissions. Upon tenant default, we may experience delays and substantial costs in enforcing our rights and protecting our investment. Our business and financial condition could be materially adversely affected if any of our significant tenants were to suffer a downturn in their business, become insolvent, default under their leases, and/or fail to renew on favorable terms or at all.

The threat or occurrence of a terrorist event, particularly in New York City, may materially and adversely affect the value of our properties and our ability to generate cash flow.

A terrorist event in New York City, particularly at a high-profile property such as the Empire State Building, could materially disrupt our operations, reduce demand for our properties and Observatory, and negatively affect occupancy and rental rates.

We maintain property, business interruption and terrorism insurance for our properties, including aggregate terrorism coverage of up to $2.0 billion for the Empire State Building through a combination of commercial insurance, our captive insurance subsidiary and participation in the federal terrorism insurance program (currently extended through December 31, 2027). However, our policies are subject to deductibles, co-insurance and coverage limitations, and certain losses, including losses caused by war or certain public health events, may not be fully insured or insurable on commercially acceptable terms.

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In addition, insurance premiums may increase, coverage may become unavailable, or policy terms may become less favorable following a terrorist event or other catastrophic incident. If we experience a loss that is uninsured or exceeds our coverage limits, we could incur significant costs, experience loss of capital or property, and continue to be obligated to repay indebtedness secured by the affected property.

Risks Relating to the Real Estate Market

Adverse economic and geopolitical conditions impacting the industries of our tenants could cause reduced demand, rental rates and occupancy for our office, multifamily, and retail space.

Downturn in global, national and/or local economies that decreases prospects, demand, occupancy and rental rates for our office, multifamily and retail space can have an adverse impact on the value or price of our assets. For example, the COVID-19 pandemic impacted the entire U.S., including New York where our properties are located. Any future public health crisis or economic downturn could have significant impacts on how people live, work, and travel in ways that have affected and may in the future affect our properties. Such events can also cause delays, cost increases and/or cancellations of planned capital projects. Certain remote work practices implemented in reaction to the pandemic are still in place and have shifted employers and employees away from fully in-person work environments, and a more permanent shift of this type could have an adverse effect on the overall demand for our office space. Additionally, with increased employer flexibility to work from home, current and prospective residents may be less likely to live in dense urban centers or multifamily housing like the properties we own. These trends have impacted our results of operations since the pandemic. If these trends continue, it could impair demand and value at our properties.

As of December 31, 2025, approximately 20.1% of our commercial portfolio’s annualized rent was comprised of retail tenants. In the past, the retail industry has faced reductions in sales revenues and increase in bankruptcies throughout the United States, due to changes in consumer behavior and shift to online shopping. This has reduced rents and demand for physical retail space at street level, which typically commanded the highest rental rates per square foot in office properties. This has also reduced rents and demand for physical retail space located above or below street level. Continued reduced demand, rental rates and occupancy rates for our retail space could have a material adverse effect on our business and financial condition.

The bankruptcy or insolvency of any tenant could result in the termination of such tenant’s lease and material losses to us.

The occurrence of a tenant bankruptcy or insolvency has in the past, and could in the future, diminish or terminate the income we receive from that tenant. We may also be unable to re-lease a terminated or rejected space on favorable terms or at all. Additionally, a large number of our tenants (measured by number of tenants as opposed to aggregate square footage) are smaller businesses that generally do not have the financial strength of larger corporate tenants. Smaller businesses generally experience a higher rate of failure than large businesses, and their insolvency could have a material adverse effect on our business, results of operations, cash flow and financial condition.

Competition may impede our ability to attract or retain tenants or re-lease space and we may be required to make rent or other concessions and/or significant capital expenditures to improve our properties in order to retain and attract tenants.

The leasing of real estate in New York City and its surrounding metropolitan area is highly competitive in rental rates, location, services and property condition. We have seen increased competition from lessors in offering concessions, short term, amenities, indoor environmental quality and sustainability certifications. See Part I, ITEM 1, “Business — Competition” for more information. Increased competition challenges our ability to lease space and maximize our effective rents. Upon expiration of leases at our properties and with respect to our current vacant space, we may be required to make rent or other concessions to tenants, accommodate increased requests for renovations, build-to-suit remodeling and other improvements or provide additional services to our tenants. In addition, nine of our properties are pre-war office properties, which may require more frequent and costly maintenance to retain existing tenants or attract new tenants than newer properties. As a result, and due to the increased competition from lessors in the greater New York City area, we have made, and may have to make, significant capital or other expenditures in order to maintain the competitiveness of our properties. There can be no assurances that any such expenditure would result in higher occupancy, higher rental rates or deter existing tenants from relocating to properties owned by our competitors. If we are unable to match the competition for lack of capital or other reasons, we may fail to attract new tenants or to renew existing tenants.

We may be unable to renew leases or re-lease vacant space on favorable terms or at all as leases expire or lease vacant space after redevelopment.

As of December 31, 2025, we had approximately 0.7 million rentable square feet of vacant space in our office and

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retail properties, including properties that are under redevelopment. In addition, leases representing 5.1% and 7.3% of the square footage of the office and retail properties in our commercial portfolio will expire in 2026 and 2027, respectively. We cannot be assured that leases scheduled to expire will be renewed or that our properties will be re-leased at net effective rental rates at or above the current average. If the terms of the renewal or re-leasing are less favorable than current terms, or we fail to re-lease such spaces at all, our business, results of operations, cash flow and financial condition will be negatively affected.

The short-term nature of multifamily leases exposes us more quickly to the effects of declining market rents, potentially making our revenue more volatile.

Generally, our multifamily leases range from one to two years. If the terms of the renewal or reletting are less favorable than current terms, our business, results of operations, cash flow and financial condition will be negatively affected. Given their short-term lease structure, our multifamily rental revenues are more sensitive to market declines.

Risks Relating to Our Properties

We face various risks related to our ground leases, including those arising from breach, expiration and eminent domain proceedings, and we have no permanent economic interest in the land or improvements at such properties.

Our interests in three of our commercial office properties, 1350 Broadway, 111 West 33rd Street and 1400 Broadway, are ground leases (i.e., long-term leaseholds of the land and the improvements), rather than a fee interest in the land and the improvements. Pursuant to these ground leases, we, as tenant, perform the functions traditionally performed by owners: collect rent from our subtenants, maintain the properties and pay related expenses. We do not have a right to acquire the fee interests in these properties. The ground leases, including unilateral extension rights available to us, expire on July 31, 2050, for 1350 Broadway, December 31, 2063, for 1400 Broadway and June 10, 2077, for 111 West 33rd Street. If we are found to be in breach of any of these ground leases, the fee owner may terminate such lease, and we could lose the right to use the properties. In addition, unless we purchase the underlying fee interest in these properties or extend the terms of the ground leases on the current terms, we will lose our right to operate these properties, or continue to operate them at lower profitability. Additionally, we will not share in any increase in value of the land or improvements and will not receive any revenue from the property beyond the term of our ground leases. If the government acquires the properties under its eminent domain power, we would only be entitled to a portion of any compensation awarded. It may be more expensive for us to renew our ground leases, to the extent renewal is available at all.

We are exposed to risks associated with property development.

We have engaged, continue to engage, and may in the future engage in development activities with respect to our properties. See Part I, ITEM 1, “Business — Overview” for more information. Development subjects us to risks beyond our control, which could have a material adverse effect on our financial condition, including, without limitation, the availability and pricing of financing; availability and timing of zoning and other approvals; occupancy rates and rents; construction costs and delays, whether due to weather, labor conditions, material shortages, tariffs or otherwise, and timely lease-up. We will fail to recover expenses and management time already incurred if we abandon any then pending development.

Significant inflation could adversely affect our business and financial results.

Increased inflation has and may in the future adversely affect us by increasing costs of properties, development and renovation. In a highly inflationary environment, we may be unable to raise rental rates at or above the rate of inflation, which could reduce our profit margins. In addition, our cost of labor and materials has and may in the future increase. The terms of some of our leases may limit our ability to charge our tenants for all or a portion of such increased expenses. Our inability to pass on such increased operating expenses may reduce cash flow available to service our debt and make distributions.

We may not be able to control our operating costs, or our expenses may remain constant or increase even if income from our properties decreases.

Certain costs associated with real estate investment, such as real estate taxes, insurance and maintenance costs, generally are not reduced when a property is not fully occupied, rental rates decrease or other circumstances cause a reduction in income. The terms of our leases may also limit our ability to charge our tenants for all or a portion of these expenses. Additionally, inflation has impacted and will continue to impact property operating expenses and construction costs.

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We are exposed to risks from third-party property management services.

While we perform property management services for the majority of our properties, we use a third-party property management company to service our multifamily properties. If such third-party property management company does not perform in accordance with our contractual agreements and desired standards, we could be exposed to risks such as costs and reputational harm.

Risks Related to Our Non-Real Estate Operations

The Observatory operations at the Empire State Building may be negatively impacted by geopolitical factors, competition, adverse weather, and changes in tourist trends.

While visitor levels improved from pandemic lows, attendance and revenue remain sensitive to macroeconomic conditions, international tourism patterns, competitive attractions in New York City and weather variability. Our visitor volume has not yet fully returned to pre-pandemic 2019 levels, and our visitor volume decreased in 2025 as compared to 2024. Although we have focused on revenue per visitor and domestic demand initiatives, there can be no assurance that international visitation will recover or that overall Observatory performance will improve in future periods.

The broadcasting operations at the Empire State Building are not traditional real estate operations, and competition and changes in the broadcasting of signals over air may subject us to additional risks.

We license the use of the Empire State Building broadcasting mast to third-party television and radio broadcasters. During the year ended December 31, 2025, we derived approximately $15.4 million of revenue (excluding tenant reimbursement income) from such broadcasting licenses and related leases, as compared with about $21.0 million at its peak. Competition from other broadcasting operations has had a negative impact on revenues, and lease renewals have yielded reduced revenue, and higher operating expenses and capital expenditures. Our broadcast licensees also face a range of competition from advances in technologies and alternative methods of content delivery in their respective industries, as well as changes in consumer behavior, which may reduce the demand for over-the-air broadcast licenses. Government regulations may materially and adversely affect our broadcast revenue by reducing the demand for broadcast licenses by making more spectrum available for wireless broadband service providers.

The impairment of a significant portion of goodwill could negatively affect our results of operations and financial condition.

Our balance sheet included goodwill of approximately $491.5 million at December 31, 2025, consisting primarily of goodwill associated with our acquisition of the controlling interest in Empire State Building Company L.L.C. and 501 Seventh Avenue Associates L.L.C. On an annual basis and whenever circumstances indicate the carrying value or goodwill may be impaired, we are required to assess any such impairment and charge to operating earnings the resulting non-cash impairment. For example, during the pandemic, the closure of our Observatory caused us to perform such an assessment quarterly. See “Financial Statements — Note 4 Deferred Costs, Acquired Lease Intangibles and Goodwill” in this Annual Report on Form 10-K for further information. An impairment could have a material adverse effect on our results of operations and financial condition.

Risks Relating to Acquisitions and Dispositions

We may be unable to identify and successfully complete acquisitions, and completed acquisitions may expose us to additional risks.

We seek to acquire new properties as we are presented with attractive opportunities, but we may face significant competition from other investors, particularly private investors who can incur more leverage. We may incur significant costs and divert management attention in connection with potential acquisitions, including ones that we are unable to complete. If we successfully identify an acquisition target and close the transaction, we may spend more than budgeted to make necessary improvements to the relevant properties and be exposed to unknown liabilities, such as environmental contamination or claims from former tenants, vendors or employees.

We may acquire properties through tax deferred contribution transactions, which could result in securityholder dilution and limit our ability to sell such assets.

In the future we may acquire properties through tax deferred contribution transactions in exchange for our partnership interests, which may result in dilution to securityholders, reduction of tax depreciation we could deduct over the tax life of the

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acquired properties (as compared with an acquisition paid in cash), and requirements to protect the contributors’ tax deferral through restrictions on our disposition of the acquired properties and/or maintenance and allocation of partnership debt to the contributors to maintain their tax bases. These restrictions could limit our ability to sell an asset at a time, or on terms, that would be favorable absent such restrictions.

If we are unable to sell, dispose of or refinance one or more properties in the future, we may be unable to realize our investment objectives.

Real estate investments are relatively difficult to sell quickly. Return of capital and realization of gains from an investment generally will occur upon disposition or refinancing. In addition, the Internal Revenue Code of 1986, as amended, (the "Code") imposes restrictions on the ability of a REIT to dispose of properties that are not applicable to other types of real estate companies. We may be unable to realize our investment objectives by sale, other disposition or refinancing at attractive prices within any given period of time.

We may incur taxable capital gain on the disposition of assets due to the failure to comply with Section 1031 of the Code.

We have and in the future may dispose of properties in transactions that are intended to qualify as “like kind exchanges” under Section 1031 of the Code. It is possible that the qualification of a transaction as a like-kind exchange could be successfully challenged and determined to be currently taxable. In such case, our taxable income and earnings and profits would increase. In some circumstances, we may be required to pay additional dividends or, in lieu of that, corporate income tax, possibly including interest and penalties. As a result, we may be required to borrow funds to pay additional distributions or taxes, and any payment of taxes could cause us to have less cash available to distribute to our unitholders. In addition, if a like-kind exchange was later determined to be taxable, we may be required to amend our tax returns for the applicable year in question, including any information reports we sent our unitholders. We could also be subject to significant indemnity obligations if the applicable property was subject to a tax protection agreement.

Risks Relating to Our Indebtedness and Liquidity

Our debt, the cost of our debt and limitations in our loan documents could adversely affect us.

As of December 31, 2025, we had total debt outstanding of approximately $2.4 billion inclusive of total mortgages of approximately $629.0 million. See “Financial Statements — Note 5 Debt” in this Annual Report on Form 10-K for further information. Our organizational documents do not limit the debt we may incur, and we may incur significant additional debt to finance future acquisition and development activities. Our current and potential levels of debt, and the limitations in our loan documents could have significant adverse consequences to our cash flow and our ability to service and refinance our debt. We may be forced to dispose of one or more of our properties, possibly on disadvantageous terms. We may default on our debt obligations, in which case the lenders may accelerate our debt obligations and foreclose on any mortgaged properties. Our default on one debt with cross-default provisions could result in a default on other debt. In addition, our revolving credit facility and related term loan bear interest at a variable rate. We may incur indebtedness in the future that also bears interest at a variable rate or may be required to refinance our debt at higher rates. If any one of these events were to occur, our results of operations, cash flow, financial condition, and ability to service debt and to make distributions could be adversely affected.

Our debt includes restrictions on our financial and operational flexibility and distributions.

Our debt instruments may restrict our financial and operational flexibility. For example, our lockbox and cash management agreements may require income from our properties to be deposited directly into lockbox accounts controlled by our lenders from which we receive cash after funding of defined operating and capital costs. As a result, we may be forced to borrow additional funds in order to make distributions. Additionally, many of our debt instruments contain financial covenants that impact how we run our business, including required ratios for debt-to-assets, adjusted EBITDA to consolidated fixed charges or debt service. Our partnership agreement may restrict our ability to pay distributions if we fail to pay the cumulative distributions on preferred units. See Part II, ITEM 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources” for more information.

Mortgages expose us to foreclosure and loss of our investment in a mortgaged property.

Mortgage and other secured debt increases our risk of property losses because defaults may result in foreclosure. For tax purposes, a foreclosure generally is treated as a sale of the property for a purchase price equal to the outstanding debt. If such debt exceeds our tax basis in the property, we will recognize taxable income on foreclosure, but not receive any cash. Foreclosures could also trigger our obligations under tax protection agreements with certain legacy investors to indemnify them

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for certain taxes upon sale of specific properties where they had embedded phantom taxable income (or the failure to maintain certain levels of indebtedness). See “Financial Statements — Note 11 Related Party Transactions — Tax Protection Agreements” in this Annual Report on Form 10-K for more information.

High mortgage rates and/or unavailability of mortgage debt may make it difficult for us to finance or refinance properties, which could reduce the number of properties we can acquire, our net income and the amount of cash distributions.

If mortgage debt is unavailable at reasonable rates, we may not be able to finance the purchase of properties. If we place mortgage debt on properties, we may be unable to refinance the properties when the loans become due at comparable terms, which may result in reduced cash flows and hinder our ability to make distributions, and to raise more capital by issuing stock or borrowing money. In addition, to the extent we are unable to refinance loans, we will have fewer debt guarantee opportunities available to offer under our tax protection agreements, which could trigger our indemnification obligation.

Our growth depends on external sources of capital that are outside of our control.

Because of the distribution requirements to maintain ESRT's status as a REIT (See Part I, ITEM 1, “Business — ESRT's Tax Status as a REIT”), we may not be able to fund future capital needs, including any acquisition financing, from operating cash flow and may need to rely on third-party sources. Additionally, our access to third-party sources of capital depends, in part, on general economic and market conditions, including the cost and availability of credit, government action or inaction and its effect on the state of the capital markets, the market’s perception of our growth potential, as well as our then current financial condition. Absent needed capital, we may not be able to acquire or develop properties when opportunities exist, satisfy our debt obligations or make cash distributions to our securityholders necessary to maintain ESRT's qualification as a REIT.

Risks Relating to Disaster Recovery and Business Continuity

Natural disasters and physical climate risk could adversely impact our area and business.

Our properties are concentrated in the New York metropolitan area. Natural disasters and physical climate risks including earthquakes, storms, storm surges, tornados, floods, extreme temperatures, hurricanes and rising sea levels could cause significant damage or limit access to our properties and adversely impact the areas in which we operate. These conditions could result in declining demand for our commercial and multifamily properties, compromise our ability to operate the buildings to the requirements and parameters set forth in our leases, make insurance less affordable or available, and increase the cost of energy and utilities at our properties. Also, certain of our properties could not be rebuilt to their existing height or size under current land use laws. In that event, we may have to upgrade such property to meet code requirements. Our disaster recovery and business continuity plans may not be adequate to address these risks.

Some of our potential losses may not be covered by insurance.

Our insurance may not be adequate to cover all losses to which we are subject. Business interruption insurance generally does not include coverage for damages from a pandemic. In addition, our insurance policies include substantial self-insurance and deductibles and co-payments for certain events. See Part I, ITEM 1, “Business — Insurance” for further information. If we experience a loss that is uninsured or exceeds our policy limits, we could incur significant costs and loss of capital or property. If the damaged property is subject to recourse debt, we would continue to be liable for the debt, regardless of the property condition. Our debt instruments contain customary covenants to maintain insurance, including terrorism insurance. While we do not believe it is likely, our lenders or ground lessors could take the position that a total or partial exclusion for losses due to terrorist acts is a breach that would accelerate debt repayment or recapture ground lease positions. In addition, if they were to prevail in requiring additional coverage, it could result in substantially higher premiums. In the future, we may be unable to obtain insurance with insurers that satisfy the rating requirements in our agreements, which could give rise to a default under such agreements and/or impair our ability to refinance.

We may incur significant costs to comply with environmental laws, and environmental contamination may impair our ability to lease and/or sell real estate.

Under various federal, state and/or local laws, ordinances and regulations, as a current or former owner or operator of real property, we may be liable for costs and damages resulting from the presence or release of hazardous substances, waste, or petroleum products at, on, in, under or from such property, including costs for investigation or remediation, natural resource damages, or third-party liability for personal injury or property damage. We also may be liable for the costs of remediating contamination at off-site disposal or treatment facilities when we arrange for disposal or treatment of hazardous substances at

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such facilities, without regard to whether we comply with environmental laws in doing so. Some of our properties have been or may be impacted by contamination arising from current or prior uses of the property or adjacent properties for commercial, industrial or other purposes. Such contamination may arise from spills of petroleum or hazardous substances or releases from tanks used to store such materials. For example, a portion of the Metro Tower site, the undeveloped parcel we own adjacent to our recently sold Metro Center asset, is currently used for automobile parking and was formerly leased to a fueling facility. See Part I, ITEM 1, "Business — Environmental Matters" for further information. The presence of contamination or the failure to remediate contamination on our properties may adversely affect our ability to attract and/or retain tenants, and our ability to develop or sell or borrow against those properties. In addition to potential liability for cleanup costs, private plaintiffs may bring claims for personal injury, property damage or for similar reasons. Environmental laws also may create liens on contaminated sites in favor of the government for damages and costs it incurs to address such contamination. Moreover, if contamination is discovered on our properties, environmental laws may impose restrictions on the manner in which that property may be used or how businesses may be operated on that property.

In addition, our properties are subject to various federal, state and local environmental and health and safety laws and regulations, and noncompliance could subject us or our tenants to liability. These liabilities could affect a tenant’s ability to make rental payments to us. Moreover, changes in laws could increase the potential costs of compliance or increase liability for noncompliance. We sometimes require our tenants to comply with environmental and health and safety laws and regulations and to indemnify us for any related liabilities in our leases with them. But in the event of the bankruptcy or inability of any of our tenants to satisfy such obligations, we may be required to satisfy such obligations. In addition, we may become subject to new compliance requirements and/or new costs or taxes associated with natural resource or energy usage and related emissions (such as a carbon tax), which could increase our operating costs. See "We may incur significant costs to comply with environmental laws, for example New York City’s Local Law 97" in this section.

As the owner or operator of real property, we may also incur liability based on various building conditions. For example, environmental site assessments have identified asbestos or asbestos-containing material (“ACM”) in certain of our properties, and it is possible that other properties that we currently own or operate or acquire in the future contain ACM. See “Financial Statements — Note 9 Commitments and Contingencies – Asset Retirement Obligations” in this Annual Report on Form 10-K for more information. Environmental and health and safety laws require that ACM be properly managed and maintained and may impose fines or penalties on owners, operators or employers for non-compliance with those requirements. In addition, we may be subject to liability for personal injury or property damage sustained as a result of releases of ACM into the environment. Additionally, our current properties, or properties we acquire in the future, may contain or develop harmful mold or suffer from other indoor air quality issues, such as inadequate ventilation and contamination, which could lead to liability for adverse health effects from our tenants, employees of our tenants or others, or property damage or costs for remediation. Any liability or increased cost from the environmental risks mentioned in this section could materially and adversely affect our operations.

We may incur significant costs to comply with environmental laws, for example New York City’s Local Law 97.

We may become subject to new compliance requirements and/or new costs or taxes associated with natural resource or energy or utility usage and related emissions (such as a carbon tax), which could increase our operating costs. In particular, as the owner of large covered commercial and multifamily buildings in New York City, we are subject to Local Law 97, which establishes annual greenhouse gas emissions limits for covered buildings and imposes penalties for emissions that exceed applicable thresholds. While we currently expect, based on our present understanding of the law and implementing rules and our internal projections of building emissions, to operate within the applicable limits during the 2024–2029 enforcement period, our expectations are based on assumptions regarding building performance, tenant energy usage and utility grid emissions factors. Regulatory developments, changes in enforcement guidance, changes in building operations, tenant behavior, energy consumption patterns, or utility emissions factors could cause us to exceed emissions limits or incur additional compliance costs or penalties, which could be material.

Risks Relating to Human Capital Management

The departure of any of our key personnel could materially and adversely affect us.

Our success depends on the efforts of key personnel, particularly Anthony E. Malkin, our Chairman and Chief Executive Officer, whose leadership and national industry reputation benefits us in many ways. He has led the acquisition, operation and repositioning of our assets for more than two decades. Other members of our senior management team also have strong industry reputations and experience, which aid us in attracting, identifying and taking advantage of opportunities. The loss of the services of one or more members of our senior management team could materially and adversely affect us.

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ESRT's Chairman and Chief Executive Officer has outside business interests that take his time and attention away from us, which could materially and adversely affect us.

Under his employment agreement, Mr. Malkin has agreed to (a) devote a majority of his business time and attention to our business and (b) during, and for a time after, his employment with us to refrain from competition with us. Mr. Malkin is also permitted to devote time to his other investments to the extent such activities do not materially interfere with the performance of his duties to us. He owns interests in properties and businesses, including properties and businesses that were not contributed to us in the formation transactions, some of which are now supervised by our Company. As a result, Mr. Malkin and his affiliates have had, and may in the future have, management and fiduciary obligations that could conflict with his responsibilities to our Company. For example, in February 2023 we closed on the disposition of our retail assets located at 69-97 and 103-107 Main Street in Westport, Connecticut, to an entity affiliated with Mr. Malkin. See “Financial Statements — Note 11 Related Party Transactions” in this Annual Report on Form 10-K for further information. We may choose to moderate or omit enforcement of our rights under his employment agreement to maintain our relationship with him given his knowledge of our business, relationships with our customers, and significant equity ownership in us, and this could have a material adverse effect on our business.

Our failure to maintain satisfactory labor relations could materially and adversely affect us.

As of December 31, 2025, we have collective bargaining agreements that cover 407 employees, or 63% of our workforce, that service our portfolio. Our inability to negotiate acceptable renewals as existing agreements expire has resulted and could in the future result in strikes or work stoppages that disrupt our operations. In any such event for any extended period of time, we would likely engage temporary replacement workers, which would result in increased operating costs.

Risks Relating to Legal Compliance, Sustainability and Cybersecurity

Failure to maintain effective internal control over financial reporting could result in loss of investor confidence and adversely impact our stock price.

We are required under Section 404 of the Sarbanes-Oxley Act to maintain internal control over financial reporting that meets applicable standards. In prior periods, we identified a material weakness in our internal control over financial reporting related to information technology general controls. We implemented remediation measures to address the material weakness, which required significant management attention, time and expense. Although we believe the remediation efforts have addressed the identified material weakness, there can be no assurance that the controls we have implemented will operate effectively or that additional material weaknesses will not be identified in the future. If we fail to maintain effective internal control over financial reporting, or if additional material weaknesses are identified, we may be unable to record, process or report financial information accurately or to prepare financial statements in a timely manner. Any such failure could result in restatements, increased audit costs, regulatory scrutiny, litigation, diversion of management’s attention, loss of investor confidence and a decline in our stock price.

We face risks associated with our tenants being designated “Prohibited Persons” by OFAC and similar requirements.

The Office of Foreign Assets Control of the U.S. Department of the Treasury (“OFAC”) maintains a list of persons designated as terrorists or who are otherwise blocked or banned (“Prohibited Persons”) from conducting business or engaging in transactions in the U.S. and thereby restricts our doing business with such persons. In addition, our leases, loans and other agreements may require us to comply with OFAC and related requirements, and any failure to do so may result in a breach of such agreements. If a tenant or other party with whom we conduct business is designated a Prohibited Person, we may be required to terminate the arrangement or face penalties. Any such termination could result in a loss of revenue or otherwise negatively affect our business.

We may incur significant costs to comply with the ADA and similar laws.

Under the Americans with Disabilities Act of 1990 (the “ADA”), all public accommodations must meet federal requirements related to access and use by disabled persons. We have incurred and could again in the future be required to incur costs to bring any non-compliant property into compliance and to make modifications to our properties upon any renovation, any of which could involve substantial costs and material adverse effect on our results of operations and financial condition. See Part I, ITEM 1, “Business — Americans with Disabilities Act” for more information.

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We may become subject to litigation, which could have a material adverse effect on our financial condition.

In the past we have been, and in the future we may become, subject to litigation, including claims relating to our operations, offerings, and otherwise in the ordinary course of business. Some of these claims may result in significant defense costs and potentially significant judgments against us, some of which are not, or cannot be, insured against. We generally intend to defend ourselves vigorously; however, we cannot be certain of the ultimate outcomes of any claims that may arise in the future. Certain litigation or its resolution may affect the availability or cost of our insurance coverage, which could adversely impact our financial condition, expose us to increased uninsured risks, and/or adversely impact our ability to attract officers and directors. See “Financial Statements — Note 9 Commitments and Contingencies” in this Annual Report on Form 10-K.

Stakeholder attention to sustainability matters may impact our business.

Investors, regulators, and other stakeholders are increasingly focused on environmental, climate, and other sustainability matters. We are subject to evolving laws, regulations, and building standards, including New York City’s Local Law 97, that may require additional capital expenditures, operational changes, or reporting obligations. Compliance costs, including costs associated with emissions reduction initiatives or energy efficiency improvements, may increase over time.

We have publicly disclosed certain sustainability goals and performance metrics. These goals are based on current assumptions regarding building performance, tenant energy usage, and utility grid emissions factors, and there can be no assurance that we will achieve them. Changes in regulatory requirements, enforcement interpretations, tenant behavior, energy consumption patterns, grid decarbonization timelines, or the availability of capital may affect our ability to meet our targets or operate within applicable emissions limits.

Sustainability-related disclosure standards and expectations continue to evolve and may differ across jurisdictions and stakeholders. Our selection and application of disclosure frameworks involve judgment, and future changes in standards or interpretation could require revisions to previously disclosed information.

Failure, or perceived failure, to comply with applicable laws or to achieve our stated sustainability objectives could result in reputational harm, increased regulatory scrutiny, or litigation, and could adversely affect our stock price or cost of capital.

Cyberattacks and any failure to comply with related laws could negatively impact us.

We rely extensively on technology, both internal and outsourced, to process transactions and manage our business, making our business increasingly at risk from cyberattacks. These threats, which continue to increase in number, intensity and sophistication, include malware, ransomware, computer viruses, phishing, unauthorized access, and other vectors used by hackers, terrorists, foreign governments, and other actors. Cyber threats and attacks on our Company have included and could in the future include internal and external attempts to gain unauthorized access to our data and computer systems to disrupt our operations or the operations of our tenants and residents, destroy property, or steal confidential information. There is no guarantee that our controls or measures to prevent or mitigate such attacks will be successful. A cyberattack could compromise the confidential information of our employees, tenants, residents, customers, and vendors, and disrupt our business operations and relationships. A security breach could require us to expend significant resources to remediate and may subject us to litigation, damages, penalties, fines, governmental investigations and enforcement actions or termination of leases. Any compromise of our security could also result in a violation of applicable privacy laws (e.g., Observatory customer data, Company employee data, or residential data at multifamily properties). These consequences could result in negative legal consequences as well as significant damage to our business and financial condition and reputation. Our vendors and other parties with whom we do business face similar threats and an incident at one of these entities could adversely impact our business. These entities are typically outside our control and may have access to certain of our information with varying levels of security and cybersecurity resources. New laws and regulations related to data privacy and security pose increasingly complex compliance challenges and costs across multiple jurisdictions, which could negatively impact our business and financial condition. We have begun the use of AI capabilities in our business and operations. We may not be successful in identifying or resolving issues before they arise. There can be no assurance that we or our service providers will properly implement AI, and the failure to do so could similarly result in negative legal consequences as well as significant damage to our business and financial condition and reputation.

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The adoption of or changes in rent regulation, tenant protection and eviction laws in New York could adversely affect our residential operations and property values.

New York, where our properties are located, has enacted and may further enact, interpret or expand laws and regulations affecting residential landlords, including rent stabilization laws and the “Good Cause Eviction” law. These laws restrict, and may further restrict, the ability to increase rents, decline lease renewals, enforce contractual obligations, recover possession of units, pursue collections or charge certain fees. Although residential properties represent a small portion of our portfolio, our residential assets include rent-stabilized units and market-rate units that may be subject to Good Cause Eviction, which may limit rent increases and tenant enforcement remedies. Changes in the regulatory environment, including actions by the New York City Rent Guidelines Board, amendments to statutory thresholds or expanded enforcement efforts, could increase operating costs, constrain rent growth and adversely affect our results of operations and property values.

Government housing regulations may limit opportunities at the multifamily properties in which we invest, and failure to comply with resident qualification requirements or to extend such programs upon expiration may result in financial penalties or loss of benefits.

We own, and may acquire additional equity interests in properties that benefit from governmental programs intended to provide housing to individuals with low or moderate incomes. These governmental programs typically provide mortgage insurance, favorable financing terms, tax credits or rental assistance payments to property owners. As a condition of the initial receipt and potential extensions of assistance under these programs, the properties must comply with various requirements, which typically limit rents to pre-approved amounts and impose restrictions on resident incomes. Failure to comply with these requirements and restrictions may result in financial penalties or loss of benefits. In addition, we will typically need to obtain the approval of the applicable government agency in order to acquire or dispose of a significant interest in or manage such property. We may not always receive such approval. Upon expiration of such programs, we may choose not to seek an extension, which will result in loss of benefits and could result in negative financial impact, in particular if we cannot raise rents for such units due to other regulations related to rent control and eviction, among others.

Risks Related to ESRT's REIT Status, Our Organization and Structure

If we are treated as a corporation for U.S. federal income tax purposes, we will be subject to entity-level U.S. federal income tax, and ESRT will cease to qualify as a REIT.

We believe we qualify as a partnership for U.S. federal income tax purposes and as such are generally not subject to U.S. federal income tax on our income. Instead, each of our securityholders, including ESRT, is required to include in income its allocable share of our income. We are treated as a publicly traded partnership under the Code and accordingly will be treated and taxed as such a corporation for U.S. federal income tax purposes unless we meet certain requirements, in particular, that at least 90% of our gross income be derived from qualifying sources income, which generally includes rental income, interest, dividends, and other income from passive sources. We believe we satisfy this test, but the IRS could challenge us, and if successful, we would be subject to U.S. federal, state and local corporate income tax, which would significantly reduce our cash available to pay debt service and distributions, could have adverse tax consequences on holders of OP units, and would disqualify ESRT from REIT status.

You may be allocated more taxable income than the distributions you receive from us.

So long as we remain eligible to be treated as a partnership for U.S. federal income tax purposes, we generally are not subject to U.S. federal income tax. Rather, each holder of our OP units is required to take into account its allocable share of items of our income, gain, loss, deduction and credit for our taxable year ending within or with the taxable year of such holder in computing such holder's U.S. federal income tax liability, regardless of whether the holder has received any distributions from us. It is possible that the tax liability of such holder could exceed our cash distributions to such holder for the year, thus requiring an out-of-pocket tax payment by the holder.

Your ability to deduct certain losses allocated from us may be subject to limitations.

Your ability to utilize any tax losses or deductions generated by us may be limited under the “at risk” limitation in Section 465 of the Code, the passive activity loss limitation in Section 469 of the Code, the basis limitation of Section 704(d) of the Code, the suspension of miscellaneous itemized deductions in Section 67 of the Code, the limitation on excess business losses in Section 461 of the Code, and/or other provisions of the Code. These limitations may, among other things, prevent a holder from utilizing allocations of loss and deduction from us against income from other sources. Furthermore, your ability to utilize certain specific items of deduction may be limited under certain provisions of the Code. The application of these

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limitations depends on our current and future operations and the individual tax positions of such holders. Holders of OP units should consult with their tax advisor regarding these provisions.

Participants may recognize taxable gain resulting from a reduction in their allocable share of our liabilities or specific transactions or tax elections by ESRT.

ESRT is not required to take into account tax consequences to the other holders of OP units other than ESRT in deciding whether to undertake specific transactions or make tax elections that result in additional taxable income allocations to you or reduce your share of our liabilities. We may elect to pay down our secured debt or refinance such debt with unsecured debt, which may reduce the amount of our liabilities allocable to a holder of OP units. In addition, certain commitments in ESRT’s tax protection agreements could reduce the share of liabilities available to be allocated to holders of OP units due to our obligation to offer to the tax-protected parties opportunities to guarantee certain debt. Over time, depreciation, capital improvements and debt amortization and repayment, among other things, may also reduce the share of our liabilities allocated to a holder of OP units. Any such reductions in the share of our liabilities that exceeds the holder's U.S. federal income tax basis in its OP units is treated as taxable gain from sale or exchange of such units.

Failure of ESRT to qualify as a REIT would have a material adverse effect on us.

We must rely on ESRT, as our general partner, to manage our affairs and business. ESRT is subject to risks that may affect its financial and other conditions, including particularly adverse consequences if it fails to qualify as a REIT for U.S. federal income tax purposes. ESRT's qualification as a REIT is governed by highly technical and complex provisions of the Code for which there are only limited judicial or administrative interpretations and depends on various facts and circumstances that are not entirely within its control. In addition, legislation, new regulations, administrative interpretations or court decisions may significantly change the relevant tax laws and/or the U.S. federal income tax consequences of qualifying as a REIT. Thus, while we and ESRT intend to operate so that ESRT will qualify as a REIT, there can be no assurance that ESRT will so qualify for any particular year. These considerations also might restrict the types of assets that we can acquire in the future. If, with respect to any taxable year, ESRT fails to maintain its qualification as a REIT and does not qualify under statutory relief provisions, it could not deduct distributions to shareholders in computing its taxable income and would have to pay U.S. federal income tax on its taxable income at regular corporate rates and thus reduce funds available for distribution and debt service, and ESRT would not be required to make distributions until it re-qualified as a REIT which would not be permitted for the four taxable years following the taxable year of its disqualification, unless it gained relief under relevant statutory provisions.

To enable ESRT to comply with REIT requirements, we may have to forego and/or liquidate otherwise attractive investments or borrow funds and we may be subject to tax.

To qualify as a REIT (and avoid certain taxes to which it would be subject notwithstanding its status as a REIT), ESRT must meet, on an ongoing basis, certain tests regarding the nature and diversification of its assets and its income. Because substantially all of ESRT's assets consists of our OP units, and substantially all of ESRT's income consists of income allocations with respect to such units, ESRT's ability to satisfy these tests will depend on the composition of our assets and income. Similarly, in order to be treated as a partnership for U.S. federal income tax purposes, we must meet certain annual tests relating to the sources of our gross income. In order to meet these tests and to allow ESRT to meet these tests, we may be required to forego investments that we otherwise would make or liquidate otherwise attractive investments.

ESRT intends to distribute its taxable net income to its securityholders in a manner intended to satisfy the REIT 90% distribution requirement and to avoid U.S. federal income tax and the 4% nondeductible excise tax. Refer to Part I, ITEM 1, “Business — ESRT's Tax Status as a REIT” for more information. Our partnership agreement provides that we will make sufficient distributions to ESRT to enable it to satisfy these distribution requirements. Any failure to do so will incur substantial entity level tax and/or disqualification as a REIT with the adverse tax consequences and limits on re-qualification described above in this section. As a result, we may be required to make distributions to ESRT at disadvantageous times or when we do not have funds readily available for distribution. These actions could have the effect of reducing our income and amounts available for distribution to our securityholders.

In addition, our taxable income may exceed our net income as determined by GAAP because, for example, realized capital losses will be deducted in determining our GAAP net income, but may not be deductible in computing our taxable income. In addition, we may incur nondeductible capital expenditures or be required to make debt or amortization payments, or the effect of limitations on interest (subject to an exception for an electing real property trade or business) and net operating loss deductibility under the current law, could cause our taxable income to exceed our net income as determined by GAAP. As a result, we may generate less cash flow than taxable income in a particular year and be required to use cash reserves, incur debt

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or liquidate assets at rates or times that we regard as unfavorable in order to allow ESRT to satisfy such REIT requirements and avoid such taxes.

We cannot match the transferor of particular Series 60, Series 250, or Series ES OP units with each transferee of such OP units, so we have adopted certain income tax accounting positions that could subject us to challenge by the IRS.

Because we cannot match the transferor of particular Series 60, Series 250, or Series ES OP units with each transferee of such OP units, we have adopted certain depreciation, amortization and other tax accounting positions that may not conform with all aspects of existing Treasury Regulations. A successful challenge to those positions could adversely affect the amount of tax benefit available or taxable income allocated to holders of such operating partnership units. It also could affect the timing of certain tax benefits or the amount of gain on the sale of such OP units and could have a negative impact on their value or result in audits of and adjustments to the tax returns of holders of such units. In addition, our taxable income and losses are determined and apportioned among investors using conventions we regard as consistent with applicable law. As a result, if you transfer your OP units, you may be allocated income, gain, loss and deduction realized by us after the date of transfer. Similarly, a transferee may be allocated income, gain, loss and deduction realized by us prior to the date of the transfer and, in certain circumstances, even if such a transferee receives no distributions. A transferee may also bear the cost of withholding tax imposed with respect to income allocated to a transferor through a reduction in the cash distributed to the transferee.

If we are unable to continue to lease the Empire State Building Observatory to a TRS or to maintain our broadcast licenses, in each case in a manner consistent with the IRS ruling that ESRT has received, we would be required to restructure our operations in a manner that could adversely affect the value of our OP units.

We rely upon private letter rulings from the IRS that income from our Observatory and broadcast facilities is qualifying rent for our REIT qualification. See Part I, ITEM 1, “Business — ESRT's Tax Status as a REIT.” We are entitled to rely upon these private letter rulings only to the extent that we did not misstate or omit a material fact in the ruling request and that we continue to operate in accordance with the material facts described in such request, and no assurance can be given that we will always be able to do so. If we were not able to treat the rent that our Company receives from Observatory TRS as qualifying income, we would be required to restructure how we operate the Observatory, which would likely require us to cede operating control of the Observatory by leasing the Observatory to an affiliate or third-party operator. If we were not able to treat our broadcast license fees as qualifying income for purposes of the REIT gross income tests, we would be required to enter into the license agreements through a TRS, which would cause the license fees to be subject to U.S. federal income tax and accordingly reduce the amount of our cash flow available to be distributed to our securityholders. In either case, if we are not able to appropriately restructure our operations in a timely manner, we would likely realize significant income that does not qualify for the REIT gross income tests, which could cause ESRT to fail to qualify as a REIT.

Our state and local taxes could increase due to property tax rate changes, reassessment and/or changes in state and local tax laws, which could materially and adversely affect us.

We are required to pay state and local taxes on our properties. Changes in state and local tax laws may result in an increase in our tax liability. A shortfall in tax revenues for states and municipalities in which we operate may lead to an increase in the frequency and size of such changes. In particular, the federal government has limited the ability of individuals to deduct state and local taxes on their federal tax returns, potentially leading many high-tax states to make significant changes to their own state and local tax laws. If such changes occur, we may be required to pay additional taxes on our assets or income. The real property taxes on our properties may increase as property tax rates change or as our properties are assessed or reassessed by taxing authorities. Therefore, the amount of property taxes we pay in the future may increase substantially from what we have paid in the past, which would materially and adversely affect our financial condition.

U.S. federal, state and local legislative, judicial or regulatory tax changes could have a material adverse effect on our shareholders and us.

The U.S. federal income tax rules dealing with REITs are constantly under review by persons involved in the legislative process, the IRS and the U.S. Department of the Treasury, which results in statutory changes as well as frequent revisions to regulations and interpretations, which could significantly and negatively affect ESRT’s ability to qualify as a REIT and the tax considerations relevant to an investment in us, or could cause us to change our investments and commitments.

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Tax consequences to holders of our operating partnership units and tax protection agreements triggered upon a sale or refinancing of our properties could limit our ability either to sell certain properties or engage in a strategic transaction.

As a result of the unrealized built-in gain attributable to a property at the time of contribution, some holders of operating partnership units, including ESRT's Chairman and Chief Executive Officer, Anthony E. Malkin, and our Chairman Emeritus, Peter L. Malkin, may suffer different and more adverse tax consequences than other holders of operating partnership units upon the sale or refinancing of the properties owned by us, including disproportionately greater allocations of items of taxable income and gain upon a realization event. As those holders will not receive a correspondingly greater distribution of cash proceeds, they may have different objectives regarding the appropriate pricing, timing, transaction structure and other material terms of any sale, exchange or refinancing of certain properties, or whether to sell, exchange or refinance such properties at all. As a result, the effect of certain transactions on Messrs. Malkin may influence their decisions affecting these properties and may cause such members of ESRT’s senior management team to attempt to delay, defer or prevent a transaction that might otherwise be in the best interests of our other securityholders, or to structure such transactions in ways that would mitigate the above tax consequences to Messrs. Malkin.

In connection with the formation transactions, we entered into a tax protection agreement with certain continuing investors, including members of the Malkin family, relating to specified contributed properties (the “Protected Properties”). The agreement continues to relate to 86-90 North 6th Street (which is a "substituted basis property" for Metro Center, which was sold in December 2025), 298 Mulberry Street (which is the "substituted basis property" for 10 Bank Street, which was sold in December 2022) and 1542 Third Avenue. The agreement generally restricts certain dispositions of those properties during applicable protection periods if such transactions would cause the protected parties to recognize pre-contribution built-in gain, unless required consents are obtained or the operating partnership makes payments intended to compensate the protected parties for the resulting tax liability. The agreement also includes provisions designed to mitigate taxable gain that could arise from reductions in certain protected parties’ shares of partnership liabilities, including restrictions on the prepayment or refinancing of certain indebtedness and the potential use of guarantees or deficit restoration obligations. In addition, in connection with ESRT's sale of a 9.9% fully diluted interest to Q REIT Holding LLC in 2016, we agreed, subject to specified thresholds and conditions, to indemnify QIA for certain taxes arising from dividends attributable to capital gains from the sale of U.S. real property interests. If triggered, these obligations could restrict our ability to dispose of certain assets, refinance indebtedness, or pursue strategic transactions, and could require payments that may be material.

Holders of ESRT’s Class B common stock have a significant vote in ESRT matters.

As part of our formation, we sought to give each contributing investor an option to hold equity interests which would allow such investor to vote on Company matters in proportion to such investor’s economic ownership in the consolidated entity, whether such investor elected taxable Class A common stock in ESRT or tax-deferred operating partnership units in our Company. Thus, the original investors were offered the opportunity to contribute their interests to us in exchange for a mix of one share of Class B common stock in ESRT and 49 operating partnership units in us for each 50 operating partnership units in us to which an investor was otherwise entitled. Each outstanding share of Class B common stock, when accompanied by 49 operating partnership units, entitles the holder thereof to 50 votes on all matters on which holders of Class A common stock in ESRT are entitled to vote, including the election of directors. Holders of ESRT Class B common stock may have interests that differ from holders of ESRT Class A common stock and our securityholders, including by reason of their interest in us, and may accordingly vote as a stockholder in ways that may not be consistent with the interests of holders of ESRT Class A common stock and our securityholders. This significant voting influence over certain matters may have the effect of delaying, preventing or deterring a change of control of ESRT, or could deprive holders of ESRT Class A common stock or our securityholders of an opportunity to receive a premium for their Class A common stock or units, as applicable, as part of a sale of ESRT.

The concentration of our voting power may adversely affect the ability of new investors to influence our policies.

As of December 31, 2025, ESRT’s Chairman and Chief Executive Officer, Anthony E. Malkin, together with the Malkin Group, has the right to vote 40,859,706 shares of ESRT’s common stock, which represents approximately 18.7% of the voting power of ESRT’s outstanding common stock. Consequently, Mr. Malkin has the ability to influence the outcome of matters presented to our securityholders, including the election of ESRT’s Board and approval of significant corporate transactions, including business combinations, consolidations and mergers and the determination of our day-to-day corporate and management policies.

As of December 31, 2025, QIA had a 10.76% fully diluted interest in ESRT, which represented 17.63% of the outstanding Class A common stock of ESRT. Pursuant to the terms of ESRT’s stockholders agreement with QIA, QIA generally has the right (but not the obligation) to maintain its fully diluted economic interest in ESRT by purchasing additional

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shares of ESRT’s Class A common stock when we or ESRT issue additional common equity securities from time to time. While QIA has agreed to limit its voting power on all matters presented to ESRT’s securityholders to no more than 9.9% of total number of votes entitled to be cast, QIA has also agreed to vote its shares in favor of the election of all director nominees recommended by ESRT’s Board. The interests of Mr. Malkin and QIA could conflict with or differ from your interests as a holder of our operating partnership units, and these large securityholders may exercise their right as securityholders to restrict our ability to take certain actions that may otherwise be in the best interests of our securityholders. This concentration of voting power might also have the effect of delaying or preventing a change of control that our securityholders may view as beneficial.

Conflicts of interest exist or could arise in the future between ESRT’s securityholders and OP unit holders.

Conflicts of interest exist or could arise in the future as a result of the relationships between ESRT and its affiliates, on the one hand, and our Company or any partner thereof, on the other. For example, a potential acquisition or disposition opportunity could be opportunistic to the REIT while tax disadvantageous to certain OP holders. ESRT’s directors and officers have duties to ESRT and its shareholders under applicable Maryland law in connection with their management of ESRT. At the same time, ESRT, as our general partner has fiduciary duties and obligations to us and our limited partners under Delaware law and our partnership agreement. ESRT’s fiduciary duties and obligations to us as general partner may come into conflict with the duties of ESRT’s directors and officers to ESRT, which may impede business decisions that could benefit our securityholders. Pursuant to our partnership agreement, our limited partners have agreed that in the event of a conflict in the duties owed by ESRT's directors and officers to ESRT and ESRT's securityholders and the fiduciary duties owed by ESRT, in its capacity as general partner of us, to such limited partners, ESRT will fulfill its fiduciary duties to such limited partners by acting in the best interest of ESRT's securityholders.

ESRT’s rights and the rights of ESRT’s securityholders to take action against ESRT’s directors and officers are limited, which could limit your recourse in the event of actions not in your best interest.

ESRT’s charter limits the liability of its present and former directors and officers to ESRT and its securityholders for money damages to the maximum extent permitted under Maryland law. Under current Maryland law, ESRT’s present and former directors and officers will not have any liability to ESRT or its securityholders for money damages other than liability resulting from (1) actual receipt of an improper benefit or profit in money, property or services or (2) active and deliberate dishonesty by the director or officer that was established by a final judgment and is material to the cause of action. Additionally, our partnership agreement provides for certain limitations on liability and indemnification obligations for us and our directors and officers and certain present and former members, managers, shareholders, directors, limited partners, general partners, officers or controlling persons of our predecessor. As a result, we and our securityholders may have limited rights against all such persons, which could limit your recourse in the event of actions not in your best interest.

Limits on changes in control may discourage takeover attempts beneficial to securityholders.

Provisions in our governance documents may delay or prevent a change of control over the Company or ESRT, or a tender offer, even if such action might be beneficial to our securityholders. Certain provisions in our partnership agreement may delay or make more difficult unsolicited acquisitions of us or changes of control, including, among others: redemption rights of qualifying parties; transfer restrictions on operating partnership units; ESRT’s ability, as general partner, in some cases, to amend the partnership agreement and to cause us to issue units with terms that could delay, defer or prevent a transaction or change of control without the consent of the limited partners; the right of the limited partners to consent to transfers of the general partnership interest and mergers or other transactions involving us under specified circumstances; and a redemption premium payable to the holders of our preferred units if we decide, at our option, to redeem preferred units for cash upon the occurrence of certain fundamental transactions, such as a change of control.

Certain provision’s in ESRT’s charter also may delay or prevent a change in control of ESRT, and by extension of us, including ownership restrictions, which generally limit (i) ownership to 9.8% in value or number of shares, whichever is more restrictive, of the outstanding shares of ESRT capital stock or more than 9.8% in value or number of shares, whichever is more restrictive, of the outstanding shares of ESRT common stock, except where waived by ESRT’s Board in its sole discretion, as it did with QIA, and (ii) ownership to the extent such ownership would result in ESRT owning (directly or indirectly) an interest in one of our tenants if the income derived by us from such tenant would reasonably be expected to equal or exceed the lesser of 1% of our gross income or an amount that would cause us to fail to satisfy any of the REIT gross income tests. Shares owned in violation of the ownership limit are subject to the loss of rights to distributions and voting and other penalties. Additionally, ESRT’s Board could establish a class or series of preferred stock that could, depending on the terms of such series, delay, defer or prevent a transaction or a change of control. These limitations could have the effect of discouraging a takeover or other transaction in which our securityholders might receive a premium for their securities or which holders might believe to be otherwise in their best interests.

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RisksRelatedtoourTradedOPUnits

Our cash available for distribution may not be sufficient to make distributions at expected levels, and the market price of our securities could be adversely affected by our level of cash distributions.

We intend to make distributions to our securityholders. All distributions will be made at the discretion of our sole general partner, ESRT, acting through its Board, and will depend on our earnings, financial condition, maintenance of ESRT’s REIT qualification and other factors as ESRT’s Board may deem relevant from time to time. If sufficient cash is not available for distribution from our operations, we may have to fund distributions from working capital or to borrow to provide funds for such distribution, or to reduce the amount of such distribution. We cannot assure you that our distributions will be made or sustained. Our failure to meet the market’s expectations with regard to future earnings and cash distributions likely would adversely affect the market price of ESRT’s Class A common stock and our traded OP units.

Changes in market conditions could adversely affect the market price of ESRT's Common Stock and our traded OP Units.

The following market conditions may affect the value of ESRT's Class A Common Stock and our traded OP units; the general reputation of REITs and the attractiveness of our equity securities in comparison to other equity securities; our financial performance; and general stock market conditions due to the economic environment or otherwise. The market value of ESRT's common stock and our traded OP Units is based on a number of factors, including, but not limited to, the market’s perception of the current and future value of our assets, our growth potential and our current and potential future earnings and distributions.

The future exercise of registration rights may adversely affect the market price of our securities.

In August 2016, ESRT entered into a registration rights agreement with QIA in connection with its purchase of ESRT’s Class A common stock, which requires ESRT, subject to certain conditions, to maintain an effective shelf registration statement with the SEC providing for the resale of QIA’s shares. The current registration statement filed on July 31, 2023, registers up to 29,894,869 shares. If QIA decides to sell all or a substantial portion of its shares, or there is market perception that it may intend to do so, it could have a material adverse impact on the market price of ESRT's Class A common stock and our traded OP units.

Future issuances of debt or equity securities or preferred units may be dilutive to current securityholders and may materially adversely affect the market price of our traded securities.

We or ESRT may issue debt or equity securities or make other borrowings. Our governance documents permit ESRT to issue additional capital stock or debt securities and for us to issue additional operating partnership units, in each case without the consent of our securityholders. Upon liquidation, holders of our debt securities and other loans and preferred equity holders will receive a distribution of our available assets before holders of ESRT’s common stock. We or ESRT are not required to offer additional debt or equity securities to existing ESRT securityholders or our securityholders, as applicable, on a preemptive basis. Therefore, additional ESRT common stock issuances, directly or through convertible or exchangeable securities (including operating partnership units), will dilute the holdings of ESRT’s existing common securityholders and such issuances or the perception of such issuances may reduce the market price of shares of ESRT’s common stock or our traded OP units. Additionally, ESRT’s preferred units or shares, if issued, would likely have a preference on distribution payments, periodically or upon liquidation, which could limit ESRT’s ability to make distributions to holders of shares of its common stock.

ITEM 1B. UNRESOLVED STAFF COMMENTS

As of December 31, 2025, we did not have any unresolved comments from the staff of the SEC.

ITEM 1C. CYBERSECURITY

Risk Management and Strategy

We regularly assess risks from cybersecurity threats, monitor our information systems for potential vulnerabilities and test those systems pursuant to our cybersecurity policies and procedures, which are integrated into the Company’s overall risk management framework.We use a combination of internal personnel and third-party service providers to monitor, detect and respond to potential cybersecurity threats.

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We maintain a cyber incident response plan that is reviewed periodically and tested through tabletop exercises involving management and other key personnel. We also conduct periodic testing and employee training designed to assess and enhance the effectiveness of our cybersecurity controls.

To date, cybersecurity threats, including as a result of any previous cybersecurity incidents, have not materially affected and we believe are not reasonably likely to materially affect our business strategy, results of operations or financial condition. Refer to the risk factor captioned “Cyberattacks and any failure to comply with related laws could negatively impact us.” in Part I, ITEM 1A. “Risk Factors” for additional description of cybersecurity risks and potential related impacts on the Company.

Governance

ESRT's Board of Directors oversees cybersecurity risk management, primarily through the Audit Committee. The Audit Committee receives periodic reports regarding cybersecurity risks, strategy and incidents.

Our Chief Technology Officers ("CTOs") are responsible for leading our cybersecurity risk management efforts and reports to the Audit Committee on cybersecurity matters.Our CTOs have extensive experience in information technology and cybersecurity.

ITEM 2. PROPERTIES

Summary of Office, Retail, and Multifamily Portfolio

As of December 31, 2025, our portfolio was comprised of approximately 7.9 million rentable square feet of office space and 0.8 million rentable square feet of retail space. Our portfolio was approximately 90.3% occupied and 93.6% leased, excluding properties that are under redevelopment, yielding approximately $552.0 million of annualized rent. We have 10 office properties and our retail properties are comprised of retail space at the base of our New York City office and multifamily properties, four standalone retail properties located in Manhattan and a portfolio of retail assets on North 6th Street (the "North Sixth Street Collection") in Williamsburg, Brooklyn.All properties are located in dynamic retail corridors with convenient access to mass transportation, a diverse tenant base and high pedestrian traffic. Our real estate segment includes all activities related to the ownership, management, operation, acquisition, repositioning and disposition of all of our real estate assets other than the observatory at the Empire State Building, which is included in our Observatory segment.

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The tables below present an overviewasofDecember 31, 2025.

Annualized

Rentable Percent Percent Rent per

Square Occupied Leased Annualized Occupied Number of

Office (8)

Retail Properties (8)

(1)Excludes (i) 186,226 square feet of space across the Company's portfolio attributable to building management use and tenant amenities, (ii) 85,334 square feet of space attributable to the Company's Observatory, and (iii) square footage related to the Company's residential units.

(2)Based on leases signed and commenced as of December 31, 2025.

(3)Percent occupied and percent leased exclude 109,456 rentable square feet of broadcasting and storage space.

(4)Includes occupied space plus leases signed but not commenced as of December 31, 2025.

(5)Represents annualized base rent and current reimbursement for operating expenses and real estate taxes.

(6)Represents annualized rent under leases commenced as of December 31, 2025 divided by occupied square feet.

(7)Represents the number of leases at each property or on a portfolio basis. If a tenant has more than one lease, whether or not at the same property, but with different expirations, the number of leases is calculated equal to the number of leases with different expirations.

(8)Excludes approximately 396,000 square feet of space, comprised of 368,000 square feet of office space and 28,000 square feet of retail space, related to the December 2025 acquisition of 130 Mercer Street, which will be redeveloped. As of December 31, 2025, the percent occupied and percent leased were 70.6%, which was comprised of 68.3% for office space and 100% for retail space.

(9)Denotes a ground leasehold interest in the property with a remaining term, including unilateral extension rights available to the Company, of approximately 38 years (expiring December 31, 2063).

(10)Denotes a ground leasehold interest in the property with a remaining term, including unilateral extension rights available to the Company, of approximately 51 years (expiring June 10, 2077).

(11)Denotes a ground leasehold interest in the property with a remaining term, including unilateral extension rights available to the Company, of approximately 25 years (expiring July 31, 2050).

(12)Excludes approximately 15,000 square feet of space related to the June 30, 2025 acquisition of 86-90 North 6th Street, which is under redevelopment. As of December 31, 2025, the percent occupied and percent leased were 0% and 49.5%, respectively.

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Tenant Diversification

As of December 31, 2025, our office and retail portfolios were leased to a diverse tenant base consisting of approximately 537 leases. Our tenants represent a broad array of industries as follows:

Diversification by Industry Percent (1) (2)

Arts & entertainment 3.2 %

Broadcast 1.0 %

Consumer goods 18.4 %

Finance, insurance, real estate 12.6 %

Government entity 2.2 %

Healthcare 2.0 %

Legal services 5.5 %

Non-profit 4.5 %

Professional services 8.8 %

Technology, media and advertising 16.0 %

Other 5.7 %

(1) Based on annualized rent.

(2) Includes in-place tenants at 130 Mercer Street which was acquired in December 2025 and will be redeveloped.

The following tables set forth information regarding the 10 largest office tenants and 10 largest retail tenants in our commercial portfolio based on the respective annualized rent as of December 31, 2025.

Tenant Property Lease Expiration (2)

LinkedIn Empire State Building Feb. 2026 - Aug. 2036 6.0 % 6.9 %

Centric Brands Inc. Empire State Building Oct. 2028 3.6 % 3.1 %

Burlington Merchandising Corporation 1400 Broadway Dec. 2042 2.4 % 2.3 %

Coty Inc. Empire State Building Jan. 2030 2.2 % 2.0 %

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Tenant Property Lease Expiration (2)

The TJX Companies, Inc. 250 West 57th Street Feb. 2041 6.3 % 4.6 %

Capital One, National Association 130 Mercer Street Nov. 2033 1.8 % 3.4 %

JP Morgan Chase Bank One Grand Central Place Dec. 2027 2.9 % 2.6 %

(1) Includes in-place tenants at 130 Mercer Street which was acquired in December 2025 and will be redeveloped.

(2) Expiration dates are per lease and do not assume exercise of renewal or extension options. For tenants with more than two leases, the lease expiration is shown as a range.

(3) Represents the percentage of occupied office rentable square feet of the Company's office portfolio.

(4) Represents the percentage of office annualized rent, including base rent and base rent and current reimbursement for operating expenses and real estate taxes, of the Company's office portfolio.

(5) Represents the percentage of retail occupied rentable square feet of the Company's retail portfolio.

(6) Represents the percentage of retail annualized rent, including base rent and base rent and current reimbursement for operating expenses and real estate taxes, of the Company's retail portfolio.

Lease Activity and Expirations

The following table sets forth new and renewal leases entered into at our properties, the weighted average annualized cash rent per square foot for new and renewal leases executed during the year, the previous weighted average annualized cash rent prior to the renewal or re-leasing of these leases and the percent increase in mark-to-market rent.

Year Ended December 31,

Increase in mark-to-market rent 5.2 % 3.5 % 6.5 %

The following tables set forth a summary schedule of expirations for leases in place as of December 31, 2025 plus available space for each of the ten calendar years beginning with the year ended December 31, 2026 at the office and retail properties in our commercial portfolio. The information set forth in the table assumes that tenants exercise no renewal options and/or early termination rights.

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Office and Retail Portfolio (1)

Signed leases not commenced 20 282,664 3.2 % — — % —

Office Properties (1),(6)

Signed leases not commenced 17 268,943 3.6 % — — % —

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Retail Properties (1)

Available — 42,975 4.7 % $ — — % $ —

Signed leases not commenced 3 13,721 0.9 % — — % —

(1)Includes in-place leases at 130 Mercer Street which was acquired in December 2025 and will be redeveloped.

(2)If a tenant has more than one lease, whether or not at the same property, but with different expirations, the number of leases is calculated equal to the number of leases with different expirations.

(3)Excludes (i) 186,226 square feet of space across the Company's portfolio attributable to building management use and tenant amenities, (ii) 85,334 square feet of space attributable to the Company's Observatory, and (iii) square footage related to the Company's residential units.

(4)Represents annualized base rent and current reimbursement for operating expenses and real estate taxes.

(5)Represents leases that are included in occupancy as of December 31, 2025 and expire on December 31, 2025.

(6)Excludes (i) retail space in our Manhattan office properties and (ii) the Empire State Building broadcasting licenses and Observatory operations.

Portfolio Transaction Activity

In December 2025, we closed on the sale of an office property, Metro Center, in Stamford, Connecticut at a sale price of $64.0 million in addition to a release to us of approximately $6.2 million of restricted cash previously held in escrow. In connection with this sale we repaid the related $71.6 million mortgage.

In December 2025, we closed on the acquisition of 130 Mercer Street (555-557 Broadway, "The Scholastic Building"), located in the SoHo submarket of Manhattan, for a purchase price of $386.0 million.

In June 2025, we closed on the acquisition of two retail properties on North 6th Street in Williamsburg, Brooklyn for a purchase price of $31.0 million.

In September and October 2024, we closed on the acquisition of a portfolio of retail properties on North 6th Street in Williamsburg, Brooklyn for an aggregate purchase price of $195.0 million.

In March 2024, we executed a buyout of the 10% non-controlling interest in two of our multifamily properties located at 561 10th Avenue and 345 East 94th Street in Manhattan for $14.2 million in cash and the assumption of $18.0 million of in-place debt and now own 100% of the ownership interests in these assets.

In September 2023, we closed on the acquisition of a Williamsburg retail property located on the corner of North 6th Street and Wythe Avenue in Brooklyn, New York, for a purchase price of $26.4 million.

In April 2023, we closed on the sale of 500 Mamaroneck Avenue in Harrison, New York at a gross asset valuation of $53.0 million.

In February 2023, we closed on the sale of 69-97 and 103-107 Main Street in Westport, Connecticut at a gross asset valuation of $40.0 million.

Net Operating Income ("NOI") from our office, retail, multifamily, and Observatory operations were approximately

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57%, 16%, 5%, and 22% of total NOI, respectively, after the effect of the 2025 acquisitions and disposition, through an implied annualized NOI for 130 Mercer derived from its purchase price and Asset Value calculated in accordance with our credit facility agreement, and the removal of Metro Center NOI. See Part II, ITEM 7, "Management's Discussion and Analysis of Financial Condition of Results of Operations — Net Operating Income" for the definition of NOI and a reconciliation to net income, the most directly comparable GAAP measure, to NOI.

Refer to "Financial Statements — Note 3 Acquisitions and Dispositions" in this Annual Report on Form 10-K for additional information.

ITEM 3. LEGAL PROCEEDINGS

Refer to “Financial Statements — Note 9 Commitments and Contingencies” in this Annual Report on Form 10-K for a description of any pending legal proceedings.

ITEM 4. MINE SAFETY DISCLOSURE

Not applicable.

PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market Information

We have four series of partnership units ("OP Units") - Series PR OP Units, Series ES OP Units, Series 60 OP Units and Series 250 OP Units. The Series ES OP Units, Series 60 OP Units and Series 250 OP Units (together, the "traded OP units") are listed on the NYSE Arca, Inc. exchange ("NYSE Arca") under the symbols "ESBA," "OGCP," and "FISK," respectively. The Series PR OP Units are not listed on any exchange and are not traded.

On February 24, 2026, the last sales price on the NYSE Arca for our Series ES OP Units, Series 60 OP Units and Series 250 OP Units was $5.80, $5.59 and $5.55, respectively, per unit.

Holders

As of February 24, 2026, we had approximately 529 registered holders of Series PR OP Units, 714 registered holders of Series ES OP Units, 207 registered holders of Series 60 OP Units and 157 registered holders of Series 250 OP Units. Certain OP Units are held in "street" name and accordingly, the number of beneficial owners of such OP Units is not known or included in the foregoing totals.

Distributions

ESRT intends to pay regular quarterly dividends to holders of its Class A common stock and Class B common stock, at least to the extent of its taxable income or as required to maintain its qualification as a REIT. Any distributions we or ESRT pay in the future will depend upon our taxable income, actual results of operations, economic conditions and other factors that could differ materially from our current expectations. Our actual results of operations will be affected by a number of factors, including the revenue we receive from our properties, our operating expenses, interest expense, the ability of our tenants to meet their obligations and unanticipated expenditures.

ESRT declared dividends of $0.035 per share for each quarter of 2025, which equates to an annualized rate of $0.14 per share.

We and ESRT's Board will continue regular reviews of our dividend and capital allocation policies. Distributions declared by us will be authorized by ESRT's Board in its sole discretion out of funds legally available therefore and will be dependent upon a number of factors, including restrictions under applicable law, our capital requirements and the distribution requirements necessary to maintain ESRT's qualification as a REIT. See ITEM 1A, "Risk Factors," and ITEM 7, "Management's Discussion and Analysis of Financial Conditions and Results of Operations," of this Annual Report on Form

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10-K, for information regarding the sources of funds used for dividends and for a discussion of factors, if any, which may adversely affect our ability to make distributions to our securityholders.

Recent Sales of Unregistered Securities Use of Proceeds from Registered Securities

Not applicable.

Repurchases of Equity Securities Stock and Publicly Traded Operating Partnership Unit Repurchase Program

ESRT's Board of Directors authorized the repurchase of up to $500.0 million of ESRT Class A common stock and our Series ES, Series 250 and Series 60 operating partnership units from January 1, 2024 through December 31, 2025. Upon expiration of this program, ESRT's Board of Directors authorized the repurchase of up to $500.0 million of ESRT Class A common stock and our Series ES, Series 250 and Series 60 operating partnership units during the period from January 1, 2026 through December 31, 2027. Under the program, ESRT may purchase ESRT Class A common stock and we may purchase our Series ES, Series 250 and Series 60 operating partnership units in accordance with applicable securities laws from time to time in the open market or in privately negotiated transactions. The timing, manner, price and amount of any repurchases will be determined by ESRT and us at our discretion and will be subject to stock price, availability, trading volume, general market conditions, and applicable securities laws. The authorization does not obligate ESRT or us to acquire any particular amount of securities, and the program may be suspended or discontinued at ESRT's and our discretion without prior notice. As of December 31, 2025, we had $491.9 million remaining of the authorized repurchase amount for the 2024-2025 period.

The following table summarizes ESRT's repurchases of equity securities in each of the three months ended December 31, 2025 under the repurchase program for the 2024-2025 period.

There were no repurchases of equity securities yet under the new 2026-2027 repurchase program. See "Financial Statements — Note 10 Equity" in this Annual Report on Form 10-K.

ITEM 6. [RESERVED]

Not applicable.

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Unless the context otherwise requires or indicates, references in this section to "we," "our," and "us" refer to Empire State Realty OP, L.P. and its consolidated subsidiaries. The following discussion and analysis should be read in conjunction with our consolidated financial statements as of December 31, 2025 and 2024 and for the years ended December 31, 2025, 2024 and 2023 and the notes related thereto which are included in this Annual Report on Form 10-K.

FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Exchange Act. We intend these forward-looking statements to be covered by the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are not historical facts and can generally be identified by words such as “anticipate,” “believe,” “expect,” “intend,” “plan,” “project,” “estimate,” “may,” “will,” “should,” “would,” and similar expressions. Forward-looking statements are based on our current expectations and assumptions and are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied.

Forward-looking statements are based on our current expectations and assumptions and are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied. These risks and uncertainties include, among others: economic and market conditions (including the impact of catastrophic events, pandemics, extreme weather, terrorism, armed hostilities, cybersecurity threats and other technology disruptions); increased costs due to tariffs or other economic factors; changes in the New York City office, retail and tourism markets (including changes in the use of office space and remote work); leasing activity, tenant defaults, early terminations and renewals, occupancy levels and rental rates; performance of the Observatory (including tourism levels, currency and geopolitical impacts, weather and competition); interest rate volatility and capital markets conditions, including our ability to refinance, restructure or extend indebtedness; real estate valuation declines and potential impairment charges; our ability to execute capital projects and complete acquisitions on acceptable terms; risks relating to governmental regulation, environmental and climate-related requirements (including Local Law 97), and our ability to achieve sustainability goals and metrics; risks relating to our ground leases; our ability to maintain our qualification as a REIT; potential taxable gain arising from transactions structured to qualify under Section 1031; legal proceedings; and risks relating to our disclosure controls and internal control over financial reporting. For a discussion of these and other factors, see "Item 1A. Risk Factors" in this report. Any forward-looking statement speaks only as of the date of this report. We undertake no obligation to update or revise any forward-looking statement to reflect subsequent events or circumstances, except as required by law.

Overview

2025 Highlights

•Net income attributable to the Company of $68.8 million.

•Core Funds From Operations ("Core FFO") of $234.2 million attributable to common unitholders.

•Signed a total of 1,009,009 rentable square feet of new, renewal and expansion leases.

•In June 2025, we closed on the acquisition of two retail properties on North 6th Street in Williamsburg, Brooklyn for a purchase price of $31.0 million.

•In December 2025, we closed on the acquisition of 130 Mercer Street, located in the SoHo submarket of Manhattan, for a purchase price of $386.0 million.

Results of Operations

Overview

The discussion below relates to the financial condition and results of operations for the years ended December 31, 2025 and 2024. For a discussion of our 2023 financial results as compared to our 2024 financial results, please see our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.

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

The following table summarizes the historical results of operations:

Years Ended December 31,

Revenues:

Operating expenses:

Other income (expense):

Net income attributable to non-controlling interests — — — (4) — (4) 4 100.0 %

Real Estate Segment

Rental Revenue

The increase in rental revenue during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 was primarily attributable to a $7.6 million increase in tenant reimbursement income and $5.9 million increase due to higher base rent from new or renewed tenants. The increases were partially offset by a net $1.9 million decrease in revenue from our recent transaction activity as disclosed in "Financial Statements - Note 3. Acquisitions and Dispositions" in this Annual Report on Form 10-K.

Property Operating Expenses

The increase in property operating expenses during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 was primarily due to higher cleaning-related payroll costs, utilities costs, and repair and maintenance costs in 2025 relating to increased building utilization and certain local law compliance costs. The increases were partially offset by a net decrease in property operating expenses from our recent transaction activity as disclosed in "Financial Statements - Note 3. Acquisitions and Dispositions" in this Annual Report on Form 10-K.

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Real Estate Taxes

The increase in real estate taxes during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 was primarily attributable to higher assessed values for multiple properties, partially offset by a net decrease from our recent transaction activity as disclosed in "Financial Statements - Note 3. Acquisitions and Dispositions" in this Annual Report on Form 10-K.

Depreciation and Amortization

Depreciation and amortization increased during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 primarily due to depreciation on building and tenant improvement assets placed in service as a result of our increase in leasing activity. The remaining activity relates to our recent transaction activity as disclosed in "Financial Statements - Note 3. Acquisitions and Dispositions" in this Annual Report on Form 10-K.

Interest Income

The decrease in interest income during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 is primarily due to lower cash balances due to unlevered property acquisitions during 2024 and 2025, the paydown of the $120.0 million revolving credit facility and the $100.0 million Series A senior unsecured notes in March 2025. See "Financial Statements — Note 5. Debt" in this Annual Report on Form 10-K.

Gain on Sale/Disposition of Property

The gain on disposition activity for the year ended December 31, 2025 relates to the disposition of Metro Center in Stamford, Connecticut as disclosed in "Financial Statements - Note 3. Acquisitions and Dispositions" in this Annual Report on Form 10-K. The gain on disposition activity for the year ended December 31, 2024 relates to the derecognition of assets and certain liabilities in connection with the consensual foreclosure of First Stamford Place in Stamford, Connecticut.

Observatory Segment

Observatory Revenue

Observatory revenues were lower due to lower visitation during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024, primarily due to lower levels of international tourism in 2025 as compared to 2024. While observatory revenues declined due to lower levels of international tourism, this was partially offset by an increase in domestic visitation and overall revenue per visitor for the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024.

Observatory Expenses

The increase in Observatory expenses during the twelve months ended December 31, 2025 compared to the twelve months ended December 31, 2024 was driven by increased costs such as marketing and maintenance costs.

Liquidity and Capital Resources

Liquidity is a measure of our ability to meet potential cash requirements, including ongoing commitments to repay borrowings, fund and maintain our assets and operations, including lease-up costs, fund our redevelopment and repositioning programs, acquire properties, make distributions to our securityholders and fulfill other general business needs. Based on the historical experience of our management and our business strategy, in the foreseeable future we anticipate we will generate positive cash flows from operations. In order for ESRT to qualify as a REIT, ESRT is required under the Internal Revenue Code of 1986 to distribute to its stockholders, on an annual basis, at least 90% of its REIT taxable income, determined without regard to the deduction for dividends paid and excluding net capital gains. We expect to make quarterly distributions, as required, to our securityholders.

While we may be able to anticipate and plan for certain liquidity needs, there may be unexpected increases in uses of cash that are beyond our control and which would affect our financial condition and results of operations. For example, we may be required to comply with new laws or regulations that cause us to incur unanticipated capital expenditures for our properties, thereby increasing our liquidity needs. Even if there are no material changes to our anticipated liquidity requirements, our sources of liquidity may be fewer than, and the funds available from such sources may be less than, anticipated or needed. Our primary sources of liquidity will generally consist of cash on hand, cash generated from our operating activities, debt issuances, common and/or preferred equity issuances and unused borrowing capacity under our unsecured revolving credit facility. We expect to meet our short-term liquidity requirements, including distributions, operating expenses, working capital, debt service, and capital expenditures from cash flows from operations, cash on hand, debt issuances, common and/or

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preferred issuances and available borrowing capacity under our unsecured revolving credit facility. The availability of these borrowings is subject to the conditions set forth in the applicable loan agreements. We expect to meet our long-term capital requirements, including acquisitions, redevelopments, repositioning and capital expenditures through our cash flows from operations, cash on hand, our unsecured revolving credit facility, mortgage financings, debt issuances, common and/or preferred equity issuances and asset sales. Our properties require periodic investments of capital for individual lease related tenant improvements allowances, general capital improvements and costs associated with capital expenditures. Our overall leverage will depend on our mix of investments and the cost of leverage. ESRT's charter does not restrict the amount of leverage that we may use.See ITEM 1A. "Risk Factors — Risks Relating to Our Indebtedness and Liquidity" in this Annual Report on Form 10-K for more information.

At December 31, 2025, we had approximately $132.7 million available in cash and cash equivalents and there was $475.0 million available under our unsecured revolving credit facility.

At December 31, 2025, we had approximately $2.4 billion of total consolidated indebtedness outstanding, with a weighted average interest rate of 4.48% and a weighted average maturity of 4.8 years. As of December 31, 2025, excluding debt amortization, we have a debt maturity of:

Year Amortization Maturities Total

As of December 31, 2025, interest expense obligations from 2026 through 2030 and thereafter amounts to approximately $515.4 million.

In connection with our three ground leases (i.e. long-term leaseholds of the land and the improvements) at 1350 Broadway, 111 West 33rd Street and 1400 Broadway, we also have contractual rent obligations totaling $65.2 million as of December 31, 2025, of which $7.4 million is due within the next five years.

Portfolio Transaction Activity

Refer to Part I. ITEM 2. "Properties - Portfolio Transaction Activity" for a summary of our portfolio transaction activity.

Refer to "Financial Statements - Note 3 Acquisitions and Dispositions" in this Annual Report on Form 10-K.

Unsecured Revolving Credit and Term Loan Facilities

In November 2025, we entered into an amended and restated credit agreement with Wells Fargo Bank, National Association, as administrative agent, and the other lenders party thereto, that amends and restates the credit agreement dated March 19, 2020, which governs our senior unsecured term loan credit facility (the “Wells Term Loan Facility”). The Wells Term Loan Facility is comprised of a $245.0 million senior unsecured term loan facility and matures on January 15, 2031.

In May 2025, we entered into a first amendment to our second amended and restated credit agreement, dated March 8, 2024, with Bank of America, N.A., as administrative agent and other lenders party thereto, which governs our BofA Credit Facilities. The first amendment amends certain sustainability margin adjustment terms. No other changes were made to the amount of the commitments, the maturity date of the outstanding loans or the covenants.

In March 2024, we closed a $715.0 million, five-year unsecured credit agreement which consists of a $620.0 million revolver and a $95.0 million term loan facility, each of which mature on March 8, 2029, inclusive of the extension periods. On March 18, 2025, we repaid the $120.0 million borrowings previously drawn on the Revolving Credit Facility. As of December 31, 2025, we had $145.0 million borrowings under the Revolving Credit Facility and $95.0 million under the BofA Term Loan Facility. See "Financial Statements — Note 5 Debt" in this Annual Report on Form 10-K for a summary of our unsecured revolving credit and term loan facilities.

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Financial Covenants

As of December 31, 2025, we were in compliance with the following financial covenants related to our unsecured facilities:

Financial Covenant Required December 31, 2025 In Compliance

Maximum total leverage < 60% 36.4 % Yes

Maximum secured leverage < 40% 10.2 % Yes

Minimum fixed charge coverage > 1.50x 3.0x Yes

Minimum unencumbered interest coverage > 1.75x 4.4x Yes

Maximum unsecured leverage < 60% 35.4 % Yes

Mortgage Debt

As of December 31, 2025, mortgage notes payable, net, amounted to $619.3 million. Our next mortgage debt maturity is for $50.0 million in April 2026.

In December 2025, we repaid the $71.6 million mortgage debt in connection with the sale of Metro Center, in Stamford, Connecticut.

In April 2024, we worked with the First Stamford Place mortgage lender to structure a consensual foreclosure. On May 22, 2024, a receiver was appointed and we ended our management of the property. On February 5, 2025, the consensual foreclosure was completed, title of the property was transferred to the mortgage lender and we were released of our mortgage obligation.

See "Financial Statements — Note 5 Debt" in this Annual Report on Form 10-K for more information on mortgage debt.

Senior Unsecured Notes

In December 2025, we closed on the issuance and sale of $175.0 million aggregate principal amount of 5.47% Series L Notes that mature on January 7, 2031 in a private placement transaction.

In March 2025, the Series A senior unsecured notes matured and the aggregate principal amount of $100.0 million was repaid. The notes had a stated interest rate of 3.93%.

See "Financial Statements — Note 5 Debt" in this Annual Report on Form 10-K for more information on senior unsecured notes.

Leverage Policies

We expect to employ leverage in our capital structure in amounts determined from time to time by ESRT's Board of Directors.In the evaluation of our level of indebtedness, ESRT's Board of Directors will consider a number of factors including the mix of recourse or non-recourse debt and cross-collateralized debt, mix of fixed or floating rate debt, and cost of leverage. ESRT's charter and bylaws do not limit the amount or percentage of indebtedness that we may incur nor do they restrict the form in which our indebtedness will be taken. ESRT's overall leverage will depend on our mix of investments and the cost of leverage. ESRT's Board of Directors may from time to time modify our leverage policies in light of the then-current economic conditions, access to and relative costs of debt and equity capital, market values of our properties, general market conditions for debt and equity securities, fluctuations in the market price of ESRT's common stock and our traded OP units, growth and acquisition opportunities and other factors. See ITEM 1A. "Risk Factors — Risks Relating to Our Indebtedness and Liquidity" in this Annual Report on Form 10-K for more information.

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Capital Expenditures

The following tables summarize our tenant improvement costs, leasing commission costs and our capital expenditures for each of the periods presented (dollars in thousands, except per square foot amounts).

Office Properties(1)(2)

Years Ended December 31,

Percentage of new cash rent over previously escalated rents 8.4 % 5.5 % 9.5 %

Leasing commission costs per square foot(5) $ 20.73 $ 19.46 $ 19.51

Retail Properties(1)(2)

Years Ended December 31,

Number of leases signed(4) 16 9 8

Leasing commission costs per square foot(5) $ 49.40 $ 74.29 $ 54.62

_______________

(1)Office activity excludes an aggregate of 475,442, 475,744, and 498,682 rentable square feet of retail space in our office properties in 2025, 2024 and 2023, respectively, that is included in the retail activity for the respective years.

(2)The tables above exclude our multifamily properties.

(3)The number of leases signed include "Early Renewals" which are leases signed over two years prior to the lease expiration.

(4)Presents a renewed and expansion lease as one lease signed.

(5)Presents all tenant improvement and leasing commission costs as if they were incurred in the period in which the lease was signed, which may be different than the period in which they were actually paid.

(amounts in thousands) Years Ended December 31,

_______________

(1)Includes all capital expenditures, excluding tenant improvements and leasing commission costs.