NYSE: BXP

We are a full-service real estate company, with substantial in-house expertise and resources in acquisitions, development, financing, capital markets, construction management, property management, marketing, leasing, accounting, risk management, tax and legal services. For this reason, we refer to our tenants as “clients” due to the many facets of our continuous engagements with them, which span beyond the usual tenant/landlord relationship. Throughout this Annual Report, we use the terms “tenant” and “client” interchangeably.

BXP manages BPLP as its sole general partner. Our principal executive office and Boston regional office are located at The Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199 and our telephone number is (617) 236-3300. In addition, we have regional offices at 2800 28th Street, Santa Monica, California 90405, 599 Lexington Avenue, New York, New York 10022, Two Embarcadero Center, San Francisco, California 94111, 1001 Fourth Avenue, Seattle, Washington 98154 and 2200 Pennsylvania Avenue NW, Washington, DC 20037.

Our internet address is http://www.bxp.com. On our website, you can obtain free copies of our Annual Reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, including exhibits, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission, or the SEC. You may also obtain BXP’s and BPLP’s reports by accessing the EDGAR database at the SEC’s website at http://www.sec.gov, or we will furnish an electronic or paper copy of these reports free of charge upon written request to: Investor Relations, BXP, Inc., Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199. “Boston Properties” is a registered trademark, BXP is a registered trademark, and the “bxp” logo is a registered trademark, in all cases, owned by BPLP.

Boston Properties Limited Partnership

BPLP is a Delaware limited partnership organized in 1997, and the entity through which BXP conducts substantially all of its business and owns, either directly or through subsidiaries, substantially all of its assets. BXP is the sole general partner of BPLP and, as of February 20, 2026, the owner of approximately 89.4% of the economic interests in BPLP. Economic interest was calculated as the number of common partnership units of BPLP

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owned by BXP as a percentage of the sum of (1) the actual aggregate number of outstanding common partnership units of BPLP and (2) the number of common units issuable upon conversion of all outstanding long term incentive plan units of BPLP (“LTIP Units”), for which all performance conditions have been satisfied for such conversion. We exclude from (1) and (2) above other LTIP Units issued in the form of Multi-Year Long-Term Incentive Plan Awards in 2024 or later (“MYLTIP Awards or MYLTIP Units”) and 2025 Outperformance Plan Awards (“2025 OPP Awards or 2025 OPP Units”), which remain subject to performance conditions. An LTIP Unit is generally the economic equivalent of a share of BXP’s restricted common stock, although LTIP Units issued in the form of MYLTIP Awards and 2025 OPP Awards are only entitled to receive one-tenth (1/10th) of the regular quarterly distributions (and no special distributions) prior to being earned.

Transactions During 2025

Acquisitions

During the year ended December 31, 2025, we acquired 2100 M Street, a vacant office building, located in Washington, DC, for a purchase price, including transaction costs, of approximately $55.9 million of cash. We intend to redevelop this site in the future (See Note 3 to the Consolidated Financial Statements).

Dispositions and Impairments

During the year ended December 31, 2025, excluding our unconsolidated joint ventures, we completed eight sales transactions for an aggregate gross sales price of approximately $702.6 million, resulting in net proceeds of approximately $682.5 million and gains on sales of real estate of $175.0 million and $177.6 million for BXP and BPLP, respectively (See Note 3 to the Consolidated Financial Statements). .

During the year ended December 31, 2025, we evaluated the consolidated properties approved by BXP’s Board of Directors (or a committee thereof) for sale to third-parties, which resulted in recognized impairment losses of approximately $85.8 million and $82.9 million for BXP and BPLP, respectively (See Notes 2 and 3 to the Consolidated Financial Statements).

Developments/Redevelopments

During the year ended December 31, 2025, we commenced development/redevelopment of four properties, including 343 Madison Avenue in New York City, New York, aggregating approximately 1.9 million in estimated net rentable square feet when complete. Our share of the aggregated estimated total investment to complete these properties is approximately $2.1 billion. We also partially or fully placed in-service four properties that totaled approximately 727,000 net rentable square feet (See Notes 3 and 6 to the Consolidated Financial Statements).

As of December 31, 2025, we had eight properties under construction/redevelopment, aggregating approximately 3.5 million in estimated net rentable square feet when completed. We estimate our share of the aggregate estimated total investment to complete these projects is approximately $3.9 billion, of which approximately $2.5 billion remained to be invested as of December 31, 2025. The total development pipeline, including office, laboratory/life sciences and retail developments, but excluding our residential developments, is 61% pre-leased as of February 20, 2026. For a detailed list of the properties under construction/redevelopment see “Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Debt

During the year ended December 31, 2025, BXP further strengthened its balance sheet by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, excluding our unconsolidated joint ventures, our debt market activities totaled approximately $4.2 billion, underscoring BXP’s consistent access to debt capital. For additional details on each of the transactions listed below, refer to Note 7 to the Consolidated Financial Statements.

Notable transactions during 2025 include:

•Repaid $850.0 million of 3.20% unsecured senior notes due January 15, 2025,

•Upsized the unsecured commercial paper program from $500.0 million to $750.0 million in March 2025,

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•Extended the maturity date for the $700.0 million unsecured term loan to 2030 (inclusive of extension options) in March 2025,

•Upsized the amended and restated revolving credit agreement from $2.0 billion to $2.25 billion and extended its maturity date to 2030 in March 2025, and

•Issued $1.0 billion of 2.00% unsecured exchangeable senior notes due 2030 in September 2025.

Hedging Transaction

On April 8, 2025, BPLP entered into an interest rate swap contract with a notional amount of $300.0 million to replace $300.0 million of interest rate swap contracts that expired on April 1, 2025. The interest rate swap was entered into to fix Daily Simple SOFR, at a fixed interest rate of 3.6775% per annum for the period commencing on April 7, 2025, the effective date, and ending on April 6, 2026 (See Note 8 to the Consolidated Financial Statements).

Equity Transactions

During the year ended December 31, 2025, BXP acquired an aggregate of 291,040 common units of limited partnership interest, including a total of 87,398 common units issued upon the conversion of LTIP Units, 2012 outperformance plan awards (“2012 OPP Units”) and 2013 - 2021 multi-year, long-term incentive program awards, presented by the holders for redemption, in exchange for an equal number of shares of BXP common stock.

Investments in Unconsolidated Joint Ventures

For additional details on each of the transactions listed below, refer to Note 6 to the Consolidated Financial Statements.

During the year ended December 31, 2025, our unconsolidated joint ventures further strengthened their balance sheets by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, their debt market activities totaled approximately $1.2 billion of which our share was approximately $0.5 billion. Notable transactions during 2025 include:

•Executed a new $252.0 million non-recourse CMBS financing secured by our 7750 Wisconsin Avenue joint venture in Bethesda, Maryland in February 2025. This new loan was used to repay the existing $252.0 million construction loan. We have a 50% ownership interest in the joint venture.

•Executed a new $225.0 million construction loan secured by our 290 Coles Street joint venture in Jersey City, New Jersey in March 2025. We have a 19.46% ownership interest in the joint venture.

•Executed a new $98.7 million construction loan secured by our 17 Hartwell Street joint venture in Lexington, Massachusetts in June 2025. We have a 20% ownership interest in the joint venture.

•Executed a new $465.0 million non-recourse CMBS financing secured by our Hub on Causeway - Podium and 100 Causeway Street joint ventures in Boston, Massachusetts in October 2025. This new loan was used to repay the existing loans aggregating approximately $490.0 million. We have a 50% ownership interest in the joint ventures.

•Executed a (1) new $108.0 million senior loan and (2) $50.0 million mezzanine loan secured by our 3 Hudson Boulevard joint venture in New York City, New York in October 2025. These new loans were used to repay the existing $80.0 million loan that was provided by us to the joint venture. We have a 25% ownership interest in the joint venture and are the lender for the mezzanine loan.

•Repaid the approximately $198.4 million construction loan secured by our Dock 72 joint venture in Brooklyn, New York in October 2025. We have a 50% ownership interest in the joint venture.

During the year ended December 31, 2025, we completed three sale transactions related to our investments in unconsolidated joint ventures. Our share of the aggregate gross sales price was approximately $237.7 million, resulting in our share of net proceeds of approximately $170.2 million. We recognized gains on sales related to these transactions of approximately $53.7 million, which has been included within Loss from Unconsolidated Joint Ventures on the Consolidated Financial Statements.

During the year ended December 31, 2025, we evaluated key impairment indicators related to certain investments in unconsolidated joint ventures (See Note 2 to the Consolidated Financial Statements). This

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evaluation, including a pending offer from a third-party, resulted in our determination that the decline in value for the joint venture that owns Gateway Commons was other-than-temporary. As a result, we recognized an other-than-temporary impairment loss on our investment in Gateway Commons of approximately $145.1 million.

Noncontrolling Interest

On August 27, 2025, we acquired our partner’s 45% ownership interest in the consolidated entity that is developing the 343 Madison Avenue project located in New York City, New York for approximately $43.5 million of cash. The acquisition price equaled the partner’s aggregate unreturned capital contributions to the joint venture. Prior to the acquisition, we had a 55% ownership interest in the joint venture.

Stock Option and Incentive Plan

For additional details on each of the transactions listed below, refer to Note 15 to the Consolidated Financial Statements.

On January 22, 2025, BXP’s Compensation Committee approved the 2025 Multi-Year Long-Term Incentive Program (the “2025 MYLTIP”) awards under the BXP, Inc. 2021 Stock Incentive Plan (the “2021 Plan”) to certain executive officers of BXP. Under Accounting Standards Codification (“ASC”) 718 “Compensation – Stock Compensation,” (“ASC 718”) the 2025 MYLTIP awards have an aggregate value of approximately $12.7 million, which amount will generally be amortized into earnings under the graded vesting method.

On January 31, 2025, the three-year measurement period for our 2022 MYLTIP awards ended and, based on BXP’s absolute and relative total shareholder return (“TSR”) performance, the final payout was determined to be 59% of target, or an aggregate of approximately $5.4 million (after giving effect to employee separations). As a result, an aggregate of 177,919 2022 MYLTIP Units that had been previously granted were automatically forfeited.

On December 22, 2025, BXP’s Compensation Committee approved the 2025 OPP Awards. Under the 2025 OPP Awards, performance and service-based equity awards were granted to certain members of BXP’s senior leadership team. The awards were issued pursuant to the 2021 Plan in the form of LTIP Units and consist of an opportunity to earn up to an aggregate of 711,864 LTIP Units. The number of LTIP Units reflects the maximum that may be earned for achieving the highest level of performance and satisfying the service-based vesting requirements. Under ASC 718 the 2025 OPP Awards have an aggregate value of approximately $31.9 million, which amount will generally be amortized into earnings under the graded vesting attribution method.

Business and Growth Strategies

Business Strategies

Our primary business objective is to maximize return on investment to provide our investors with the greatest possible total return at all points of the economic cycle. Our long-term strategies to achieve this objective are:

•to target a few carefully selected dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC—and to be one of the leading, if not the leading, developers, owners and managers in each of those markets with a full-service office in each market providing property management, leasing, development, construction and legal expertise. We select markets and submarkets with a diverse economic base and a deep pool of prospective clients in various industries and where clients have demonstrated a preference for premier workplaces and other facilities. Additionally, our markets have historically been able to recruit new talent to them and help sustain job growth that results in growth in rental rates and occupancy over time;

•to emphasize markets and submarkets within those markets where the difficulty of receiving the necessary approvals for development and the necessary financing constitute high barriers to the creation of new supply, and where skill, financial strength and diligence are required to successfully develop, finance and manage high-quality office as well as selected life sciences, retail and residential space;

•to take on complex, technically challenging development projects, leveraging the skills of our management team to successfully develop, acquire or reposition properties that other organizations may not have the capacity or resources to pursue;

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•to own and develop high-quality real estate designed to meet the demands of today’s clients who require sophisticated telecommunications and related infrastructure, support services, sustainable features and amenities, including those amenities that enrich in-person experiences and support a hybrid work environment, and to manage those facilities so as to become the landlord of choice for both existing and prospective clients;

•to opportunistically acquire assets that increase our market share in the markets in which we have chosen to concentrate, as well as potential new markets, which exhibit an opportunity to improve returns through repositioning (through a combination of capital improvements and shift in marketing strategy), changes in management focus and leasing;

•to explore joint venture or lending opportunities with existing property owners located in desirable locations, who seek to benefit from the depth of development and management expertise we are able to provide and our access to capital;

•to pursue on a selective basis the sale of properties or interests therein, including core properties, to either (1) take advantage of the demand for our premier properties and realize the value we have created or (2) pare from our portfolio properties that we believe have slower future growth potential;

•to seek third-party development contracts to enable us to retain and utilize our existing development and construction management staff, especially when our internal development is less active or when new development is less-warranted due to market conditions; and

•to enhance our capital structure through our access to a variety of sources of equity and debt capital and proactively manage our debt expirations.

From time to time, in response to one or more macroeconomic or other external factors, we refine our plans for achieving one or more elements of our overall strategy. At our September 2025 Investor Day, we detailed a three-year action plan focused on near-term earnings growth by leveraging BXP's operational expertise and portfolio of premier workplaces within our core gateway markets to:

•grow occupancy;

•develop premier assets with a focus on projects underway and a selective approach to future opportunities;

•execute on a multi-year asset sales program to dispose of non-income producing land, select residential, and non-strategic and select strategic office assets, with proceeds designated to reduce leverage and fund our development pipeline; and

•secure private equity partnerships on select assets to complement other funding sources and increase investment yields.

We believe the components of this strategic action plan align with our broader, long-term strategy of maintaining leadership in core markets, prudently growing the portfolio, and disciplined capital allocation to drive shareholder value. We may achieve the goals underlying this strategic action plan through a variety of methods and the timing, extent and impact of any transactions that we have or will undertake while implementing this strategic action plan may vary and evolve.

Growth Strategies

External Growth Strategies

We believe that our development experience, our organizational depth, utilization of our joint venture partner relationships and our balance sheet position us to continue to selectively develop a range of premier workplaces, including high-rise urban developments, mixed-use developments (including office, residential and retail), low-rise suburban office and residential properties, within budget and on schedule. We believe we are also well-positioned to achieve external growth through acquisitions. From time to time, we remove from service select office assets for which we believe we have better uses, such as residential developments. Other factors that contribute to our competitive position include:

•our control of sites in our markets that could support, as of December 31, 2025, approximately 13.6 million and 4.7 million of additional square feet of new office and residential developments, respectively;

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•our reputation gained through 56 years of successful operations and the stability and strength of our existing portfolio of properties;

•our relationships with leading national corporations, universities and public institutions, including government agencies, seeking new facilities and development services;

•our relationships with nationally recognized financial institutions that provide capital to the real estate industry;

•our track record and reputation for executing acquisitions efficiently provide comfort to domestic and foreign institutions, private investors and business entities who seek to sell commercial real estate in our market areas;

•our ability to act quickly on due diligence and financing;

•our relationships with institutional buyers and sellers of high-quality real estate assets;

•our ability to procure entitlements from multiple municipalities to develop and/or sell sites and attract land owners to sell to or partner with us; and

•our relationship with domestic and foreign investors who seek to partner with companies like ours.

Opportunities to execute our external growth strategy fall into three categories:

•Development in selected submarkets. We believe the selective development of well-positioned premier workplaces, as well as residential buildings and mixed-use complexes, may be justified in certain of our markets. We believe in acquiring land after taking into consideration timing factors relating to economic cycles and in response to market conditions that should allow for its development at the appropriate time. While we purposely concentrate in markets with high barriers-to-entry, we have demonstrated throughout our 56-year history an ability to make carefully timed land acquisitions in submarkets where we can become one of the market leaders in establishing rent and other business terms. We believe that there are opportunities at key locations in our existing and other markets for a well-capitalized developer to acquire land or buildings with development or redevelopment potential.

We seek complex projects where we can add value through the efforts of our experienced and skilled management team leading to attractive returns on investment. In the past, we have been particularly successful at acquiring sites or options to purchase sites that need governmental approvals for development. Because of our development expertise, knowledge of the governmental approval process and reputation for quality development with local government regulatory bodies, we generally have been able to secure the permits necessary to allow development and to profit from the resulting increase in land value.

Our strong regional relationships and recognized development expertise have also enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn relatively significant returns on these development opportunities through multiple business cycles.

•Acquisition of assets and portfolios of assets from institutions, including lenders, or individuals. We believe that due to our size, management strength and reputation, we are well positioned to acquire portfolios of assets or individual properties from institutions or individuals if valuations meet our criteria. In addition, we believe that our market knowledge, our liquidity and access to capital may provide us with a competitive advantage when pursuing acquisitions. Opportunities to acquire properties may also come through the purchase of first mortgage or mezzanine debt. We are also able to appeal to sellers wishing to contribute on a tax-deferred basis their ownership of property for equity in a diversified real estate operating company that offers liquidity through access to the public equity markets in addition to a quarterly distribution. Our ability to offer common and preferred units of limited partnership in BPLP to sellers who would otherwise recognize a taxable gain upon a sale of assets for cash or BXP’s common stock may facilitate these types of acquisitions on a tax-efficient basis. Existing promulgated Treasury regulations may limit the tax benefits previously available to sellers in some variations of these transactions.

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•Acquisition of underperforming assets and portfolios of assets. We believe that because of our in-depth market knowledge and development experience in each of our markets, our national reputation with brokers, financial institutions, owners of real estate and others involved in the real estate market and our access to competitively-priced capital, we are well-positioned to identify and acquire existing, underperforming properties for competitive prices and to add significant additional value to such properties through our effective marketing strategies, repositioning/redevelopment expertise and a responsive property management program.

Internal Growth Strategies

We believe that opportunities will exist to increase cash flow from our existing properties through an increase in occupancy and rental rates because they are of high quality and in desirable locations. Additionally, our markets have diversified economies that have historically experienced job growth and increased use of office space, resulting in growth in rental rates and occupancy over time. Our strategy for maximizing the benefits from these opportunities is three-fold: (1) to provide high-quality property management services using our employees in order to encourage clients to renew, expand and relocate in our properties, (2) to achieve speed and transaction cost efficiency in replacing departing clients through the use of in-house services for marketing, lease negotiation and construction of tenant and capital improvements and (3) to work with new or existing clients with space expansion or contraction needs, leveraging our expertise and clustering of assets to maximize the cash flow from our assets. We expect to continue our internal growth as a result of our ability to:

•Carefully select submarkets and cultivate long-term relationships with creditworthy clients. In choosing locations for our properties, we have paid particular attention to transportation and commuting patterns, physical environment, adjacency to established business centers and amenities, proximity to sources of business growth and other local factors that we believe our clients demand.

At December 31, 2025, the weighted-average lease term of our in-place leases based on square feet, including leases signed by our unconsolidated joint ventures, was approximately 7.9 years and we continue to cultivate long-term leasing relationships with a diverse base of high-quality, financially stable clients. In 2025, we executed approximately 5.6 million square feet of leases with a weighted-average lease term of 10.1 years. Based on leases in place at December 31, 2025, leases with respect to approximately 2.6%, or approximately 1.2 million square feet, of the total square feet in our portfolio, including unconsolidated joint ventures but excluding Gateway Commons and North First Business Park, will expire in calendar year 2026.

•Directly manage our office properties to maximize the potential for client retention. We provide property management services ourselves, rather than contracting for this service, to maintain awareness of and responsiveness to client needs. We and our properties also benefit from cost efficiencies produced by an experienced work force attentive to preventive maintenance and energy management and from our continuing programs to assure that our property management personnel at all levels remain aware of their important role in client relations. In addition, we reinvest in our properties by adding new services and amenities that are desirable to our clients.

•Replace clients quickly at best available market terms and lowest possible transaction costs. We believe that we are well-positioned to attract new clients and achieve relatively high rental and occupancy rates as a result of our well-located, well-designed and well-maintained properties, our reputation for high-quality building services and responsiveness to clients, and our ability to offer expansion and relocation alternatives within our submarkets.

•Extend terms of existing leases to existing clients prior to expiration. We have also successfully structured early client renewals, which have reduced the cost associated with lease downtime while securing the tenancy of our highest quality credit-worthy clients on a long-term basis and enhancing relationships.

•Re-development of existing assets. We believe the select re-development of assets within our portfolio, where through the ability to increase the building size and/or to increase cash flow and generate appropriate returns on incremental investment after consideration of the asset’s current and future cash flows, may be desirable. This generally occurs in situations in which we are able to increase the building’s size, improve building systems, including conversion to higher yielding uses, and sustainability features, and/or add client amenities, thereby increasing client demand, generating acceptable returns

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on incremental investment and enhancing the long-term value of the property and the company. In the past, we have been particularly successful at gaining local government approval for increased density at several of our assets, providing the opportunity to enhance value at a particular location. Our strong regional relationships and recognized re-development expertise have enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn attractive returns on these development opportunities through multiple business cycles.

Sustainability

Our Strategy

We are committed to maximizing long-term value for our shareholders through, among other strategies, actively working to promote our growth and operations sustainably and responsibly across our six dynamic gateway markets. BXP’s sustainability strategy is to conduct our business, the development, ownership and operation of new and existing buildings, in a manner that contributes to positive outcomes for our clients, shareholders, employees and the communities in which we operate (collectively, our “stakeholders”). We are focused on developing and maintaining healthy, high-performance buildings, while simultaneously mitigating operational costs and the potential external impacts of energy, water, waste, and climate change. We undertake electric, steam, and natural gas efficiency projects and procurement initiatives to reduce energy-related operating expense growth and primary fossil fuel consumption. These initiatives have also contributed to lower greenhouse gas (“GHG”) emissions and compliance with building performance standards in the New York and Boston markets. Through our efforts, we demonstrate that operating and developing commercial real estate can be conducted with a conscious regard for the environment while mutually benefiting our stakeholders.

Sustainability Leadership

BXP is a widely recognized industry leader in sustainability, and our 2025 highlights include:

•BXP achieved carbon-neutral operations for GHG emissions Scopes 1 and 2

•BXP ranked among the top real estate companies in the GRESB assessment, earning a tenth consecutive 5-star rating. 2025 was the 14th consecutive year that BXP earned the GRESB “Green Star” designation

•BXP maintained an MSCI rating of “AA” and a CDP score of “B”

•BXP was named to Newsweek’s America’s Most Responsible Companies 2026 for the sixth consecutive year, ranking in the top half of 600 companies, and was also named to Newsweek’s America’s Greenest Companies 2026 with a 5-star rating

•BXP was named a Fitwel Best in Building Health Award winner by the Center for Active Design for the ninth time

•BXP earned the City of Boston’s Building Emissions Reduction and Disclosure Ordinance's (BERDO) Energy Efficiency Spotlight, highlighting our retro-commissioning efforts in Boston

•BXP was named a Sustainalytics Low Carbon Leader

•BXP continued its tenure as an inaugural Platinum Level Green Lease Leader by the Institute for Market Transformation and the U.S. Department of Energy

Our leadership position is due, in part, to our establishment of environmental goals, the periodic reporting of progress toward our goals and the achievement of these goals, which we report in an annual Sustainability & Impact Report that is made available on our website at http://www.bxp.com under the heading “Commitment”. We have publicly adopted energy, water, building certification, waste and GHG emissions goals, including a commitment to achieving carbon-neutral operations (for direct and indirect Scope 1 and Scope 2 GHG emissions) by the end of 2025 from our occupied and actively managed buildings where we have operational control. We have also provided climate-related disclosures aligned with the recommendations of the Task Force on Climate-Related Financial Disclosures (“TCFD”). Detailed information on these goals and targets and our TCFD disclosures are included in our Sustainability & Impact Reports. We expect to publish our next report in April 2026.

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The Sustainability & Impact Reports and the related information contained on our website (or that can be accessed through our website) are not incorporated by reference into this Annual Report on Form 10-K.

Sustainability Accounting Standards Board (“SASB”) Disclosures

The Real Estate Sustainability Accounting Standard issued by SASB in 2018 proposed sustainability accounting metrics designed for disclosure in mandatory filings, such as the Annual Report on Form 10-K, and serves as the framework against which we have aligned our disclosures for sustainability information. The recommended energy and water management activity metrics for the real estate industry include energy consumption data coverage as a percentage of floor area (“Energy Intensity”); percentage of the eligible portfolio that is certified ENERGY STAR® (“ENERGY STAR certified”); total energy consumed by portfolio area (“Total Energy Consumption”); water withdrawal as a percentage of total floor area (“Water Intensity”); and total water withdrawn by portfolio area (“Total Water Consumption”). Our energy and water data is collected from utility bills and submeters and is assured by an independent, third-party assurance expert, which includes all 2024 SASB energy and water metrics. During the 2025 calendar year, 64 buildings representing 50% of BXP’s total in-service portfolio were ENERGY STAR certified. A licensed professional has verified all ENERGY STAR applications.

The charts below detail our Energy Intensity, Total Energy Consumption, Water Intensity and Total Water Consumption for 2015 through 2024 for which data were available on occupied and actively managed office buildings where we had operational control.1,2,3,4,5,6

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(1)Full 2025 calendar year energy and water data will not be available and assured by a third party until April 2026. Therefore, 2024 is the most recent year for which complete and third-party assured energy and water data is available.

(2)The charts reflect the performance of our occupied and actively managed office portfolio. We define “occupied buildings” as those with no more than 50% vacancy. Actively managed office buildings are multi-tenant buildings over which we have operational control of building system performance and investment decisions. At the end of the 2024 calendar year, our occupied and actively managed office portfolio included 75 buildings totaling 39.6 million gross square feet, and it accounted for approximately 73% of BXP’s total in-service portfolio by area.

(3)Floor area is considered to have complete energy consumption data coverage when we obtain energy consumption data (i.e., energy types and amounts consumed) for all types of energy consumed in the relevant floor area during the calendar year, regardless of when such data was obtained.

(4)The scope of energy includes energy purchased from sources external to us and our clients or produced by us or our clients and energy from all sources, including fuel, gas, electricity and steam. Energy use intensity (kBtu/SF) has been weather-normalized.

(5)Water sources include surface water (including water from wetlands, rivers, lakes and oceans), groundwater, rainwater collected directly and stored by BXP, municipal water supplies or supply from other water utilities.

(6)2020 and 2021 data reflect the combined impacts of efficiency measures and reduced physical occupancy due to the COVID-19 pandemic.

Human Capital Management

As of December 31, 2025, we had 714 non-union employees and 112 union employees. Because the unions control the primary aspects of the hiring process, except as otherwise noted, all data provided in this Human Capital Management section refers to BXP’s non-union employee workforce only.

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Our operational and financial performance depends on the talents, energy, experience and well-being of our employees. Our ability to attract and retain talented people depends on a number of factors, including work environment, career development and professional training, compensation and benefits, and the health, safety and wellness of our employees.

Our workforce provides a strategic business advantage as it is one of our most valuable assets. We are committed to the quality, growth and development of our people as part of our strategy to drive long-term value for our shareholders. We aim to ensure that all employees have the opportunity to make their maximum contribution to us and to their own career goals. It has been, and will continue to be, our policy to recruit, hire, assign, promote and train in all job titles without regard to race, national origin, religion, age, color, sex, sexual orientation, gender identity, disability, protected veteran status, or any other characteristic protected by local, state, or federal laws, rules, or regulations. Our hiring practices do not, and have not, included quotas or numerical targets based on any of these characteristics.

Culture & Employee Engagement

We believe that the success of our business is tied to the quality of our workforce, and we strive to maintain a corporate environment without losing the entrepreneurial spirit with which we were founded more than 55 years ago. By providing a quality workplace and comprehensive benefit programs, we recognize the commitment of our employees to bring their talent, energy and experience to us. Our continued success will depend on our employees’ expertise and dedication. Our workforce, as referred to in this section, excludes intern employees and union employees for which the unions control primary aspects of the hiring process.

We periodically conduct employee engagement surveys to monitor our employees’ satisfaction in different aspects of their employment, including company performance, leadership, communication, career development and benefits offerings. Past employee responsiveness to the engagement surveys has been consistently high and the results help inform us on matters that our employees view as key contributors to a positive work experience. Based on the most recent employee engagement survey conducted in 2025, with a 93% response rate, the overall company-wide result was a “favorable” rating. The results affirmed that BXP is healthy across core areas such as company performance, leadership and management. We intend to continue to periodically evaluate employee engagement as needed on a meaningful basis.

Another indicator of the success of our efforts in the workplace is the long tenure of our employees. Approximately 34% of our employees have worked at BXP for ten or more years. The average tenure of our employees is approximately 9.8 years and that of our officers is 18.3 years. In 2025, our voluntary workforce turnover rate was 7.6%.

Career Development & Training

We invest significant resources in our employees’ personal and professional growth and development and provide a wide range of tools and development opportunities that build and strengthen employees’ leadership and professional skills. These development opportunities include in-person and virtual training sessions, in-house learning opportunities, various management trainings, departmental conferences, executive town halls and external programs. We foster an environment of growth and internal promotion and strive for a process that is grounded in efficiency, transparency and collaboration for our internal candidates. Open positions are posted, and employees are highly encouraged to apply for promotion within the organization. In 2025, more than 7% of our employees were promoted to elevated roles within our organization.

Compensation & Benefits

We designed our compensation program with the goal of providing a balanced and effective way of ensuring internal equity and market competitiveness in our pay practices. We have coupled external market-driven data with a comprehensive performance review assessment tool to strike the balance that best represents our compensation strategy and links pay to performance. On an annual basis, our Human Resources department evaluates market compensation ranges for each position to ensure we are appropriately compensating our employees. We believe this total rewards program directly aligns with our compensation and benefits strategy.

Our employee benefit programs are thoughtfully designed to meet the needs of our workforce by offering comprehensive and competitive programs to support our employees and their families. These programs provide flexibility and choice in coverage, valuable resources to protect and enhance financial security, and benefits that help balance work and personal life. Some of the benefits that we offer our employees include:

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•health (including telehealth), dental and vision insurance,

•employer-subsidized health savings account,

•a 401(k) plan with a generous company matching contribution,

•an employee stock purchase plan that allows employees to purchase our common stock at a discount,

•health care and dependent care flexible spending accounts,

•income protection through our sick pay, salary continuation, long-term disability policies and life insurance and AD&D insurance,

•business travel accident insurance,

•a scholarship program for the children of non-officer employees,

•tuition reimbursement,

•a commuter subsidy to encourage and support the use of public transportation,

•paid vacation, holiday, personal days, a volunteer day program, and paid parental leave to balance work and personal life,

•wellness and mental health well-being programs,

•employee assistance program,

•matching charitable gift program,

•back-up care for children and elders, and

•pet insurance.

Health, Safety & Wellness

As one of the largest publicly traded premier workplace REITs (based on total market capitalization as of December 31, 2025) in the United States, we appreciate the influence of buildings on human health and its importance to our clients and employees. The health, safety and security of our employees, clients, contractors and other visitors to our properties are our highest priority. We have implemented numerous operational measures to promote better health and safety in our buildings, including measures related to indoor air quality in our buildings.

We believe the success of our employees is dependent upon their overall well-being, including their physical health, mental health, work-life balance and financial well-being. In addition to the benefits outlined above, we also offer our employees an Employee Wellness Program, an Employee Assistance Program and a Mental Health Well-Being Program. The Employee Wellness Program was established in 2016 to encourage employees to improve their health and well-being by offering a variety of activities and engaging content to meet individual wellness goals. Qualifying program participants receive a discount on a portion of their health insurance cost. The Employee Assistance Program includes services for childcare, eldercare, personal or work-related relationships, financial planning assistance, stress management, mental health, general wellness and self-help. BXP also offers a premium mental health wellbeing program that provides online resources and support for employees facing a wide variety of issues.

Policies with Respect to Certain Activities

The discussion below sets forth certain additional information regarding our investment, financing and other policies. These policies have been determined by BXP’s Board of Directors and, in general, may be amended or revised from time to time by the Board of Directors.

Investment Policies

Investments in Real Estate or Interests in Real Estate

Our investment objectives are to provide quarterly cash dividends/distributions to our securityholders and to achieve long-term capital appreciation through increases in our value. We have not established a specific policy regarding the relative priority of these investment objectives.

We expect to continue to pursue our investment objectives primarily through the ownership of our current properties, development and redevelopment projects and other acquired properties. We currently intend to continue to invest primarily in developments of properties and acquisitions of existing improved properties or properties in

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need of redevelopment, and acquisitions of land that we believe have development potential, primarily in our existing markets of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. We have explored and may continue to explore for future investment in select domestic and international markets that exhibit these same traits. Future investment or development activities will not be limited to a specified percentage of our assets. We intend to engage in such future investment or development activities in a manner that is consistent with the maintenance of BXP’s status as a REIT for federal income tax purposes. In addition, we may purchase or lease income-producing commercial and other types of properties for long-term investment, expand and improve the real estate presently owned or other properties purchased, or sell such real estate properties, in whole or in part, when circumstances warrant. We do not have a policy that restricts the amount or percentage of assets that will be invested in any specific property, however, our investments may be restricted by our debt covenants.

We may also continue to participate with third parties in property ownership, through joint ventures or other types of co-ownership. These investments may permit us to own interests in larger assets without unduly restricting diversification and, therefore, add flexibility in structuring our portfolio.

Equity investments may be subject to existing mortgage financing and other indebtedness or such financing or indebtedness as may be incurred in connection with acquiring or refinancing these investments. Debt service on such financing or indebtedness will have a priority over any distributions with respect to BXP’s common stock. Investments are also subject to our policy not to be treated as an investment company under the Investment Company Act of 1940, as amended (the “1940 Act”).

Investments in Real Estate Mortgages and Mezzanine Debt

While our current portfolio consists primarily of, and our business objectives emphasize, equity investments in commercial real estate, we may, at the discretion of the Board of Directors of BXP, invest in mortgages and other types of real estate interests consistent with BXP’s qualification as a REIT. Investments in real estate mortgages run the risk that one or more borrowers may default under the mortgages and that the collateral securing such mortgages may not be sufficient to enable us to recoup our full investment. We may invest in participating, convertible or traditional mortgages if we conclude that we may benefit from the cash flow, or any appreciation in value of the property or as an entrance to the fee ownership. As of December 31, 2025, we had one note receivable and two related-party note receivables outstanding, which totaled approximately $37.7 million, after adjustments for financing costs and the current expected credit loss allowance.

Securities of or Interests in Entities Primarily Engaged in Real Estate Activities

Subject to the percentage of ownership limitations and gross income and asset tests necessary for BXP’s REIT qualification and our debt covenants, we also may invest in securities of other REITs, other entities engaged in real estate activities or securities of other issuers, including for the purpose of exercising control over such entities.

Dispositions

Our long-term business strategy includes selective asset sales from time to time. In general, we decide to dispose or partially dispose of properties based upon a periodic review of our portfolio and the determination by the Board of Directors of BXP that doing so is in our best interests. However, a key component of our current strategic action plan introduced at our September 2025 Investor Day is the execution of a multi-year asset sales program to generate approximately $1.9 billion in net proceeds to fund our development pipeline and reduce leverage. See “Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations” for more details on our asset sales program.

Any decision to dispose of a property or a partial interest in a property will be authorized by the Board of Directors of BXP or a committee thereof. Some holders of limited partnership interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties that differ from the tax consequences to BXP. Consequently, holders of limited partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale. Such different tax treatment derives in most cases from the fact that we acquired these properties in exchange for partnership interests in contribution transactions structured to allow the prior owners to defer taxable gain. Generally, this deferral continues so long as we do not dispose of the properties in a taxable transaction. Unless a sale by us of these properties is structured as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Code”), or in a manner that otherwise allows deferral to continue, recognition of the deferred tax gain allocable to these prior owners is generally triggered by a sale. As of December 31, 2025, we had one property that was subject to a tax protection agreement, which may limit our ability to dispose of the asset or require us to pay damages to the prior owner in the event of a taxable

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sale in violation of the agreement. The tax protection agreement expires on December 14, 2033, or earlier upon the occurrence of certain events.

Financing Policies

The agreement of limited partnership of BPLP and BXP’s certificate of incorporation and bylaws do not limit the amount or percentage of indebtedness that we may incur. Further, we do not have a policy limiting the amount of indebtedness that we may incur, nor have we established any limit on the number or amount of mortgages that may be placed on any single property or on our portfolio as a whole. However, our mortgages, credit facilities, joint venture agreements and unsecured debt securities contain customary restrictions, requirements and other limitations on our ability to incur indebtedness. In addition, we evaluate the impact of incremental leverage on our debt metrics and the credit ratings of BPLP’s publicly traded debt. A reduction in BPLP’s credit ratings could result in us borrowing money at higher interest rates.

The Board of Directors of BXP will consider a number of factors when evaluating our level of indebtedness and when making decisions regarding the incurrence of indebtedness, including the purchase price of properties to be acquired with debt financing, the estimated market value of our properties upon refinancing, the cost and effectiveness of entering into interest rate swaps, caps, floors and other interest rate hedging contracts and the ability of particular properties, and us as a whole, to generate cash flow to cover expected debt service.

Policies with Respect to Other Activities

As the sole general partner of BPLP, BXP has the authority to issue additional common and preferred units of limited partnership interest of BPLP. BXP has issued, and may in the future issue, common or preferred units of limited partnership interest to persons who contribute their direct or indirect interests in properties to us in exchange for such common or preferred units. We have not engaged in trading, underwriting or agency distribution or sale of securities of issuers other than BXP and BPLP does not intend to do so. At all times, we intend to make investments in such a manner as to enable BXP to maintain its qualification as a REIT, unless, due to changes in circumstances or to the Code, the Board of Directors of BXP determines that it is no longer in the best interest of BXP to qualify as a REIT. We may make loans to third parties, including, without limitation, to joint ventures in which we participate or in connection with the disposition of a property. We intend to make investments in such a way that we will not be treated as an investment company under the 1940 Act. Our policies with respect to these and other activities may be reviewed and modified or amended from time to time by the Board of Directors of BXP.

Governmental Regulations

General

Compliance with various governmental regulations has an impact on our business, including our capital expenditures, earnings and competitive position, which can be material. We incur costs to monitor and take actions to comply with governmental regulations that are applicable to our business, which include, among others, (1) federal securities laws and regulations, (2) applicable stock exchange requirements, and (3) federal, state and local laws and regulations related to (a) our status as a REIT and other tax laws and regulations, and (b) real property, the improvements thereon and the operation thereof, such as laws and regulations relating to the environment, health and safety, zoning, usage, building, fire and life safety codes, (4) the requirements of the Office of Foreign Assets Control of the United States Department of the Treasury and (5) the Americans with Disabilities Act of 1990. In addition to the discussion below, see “