Equity Residential and AvalonBay (AVB) to merge; Ben Schall named CEO

Rhea-AI Filing Summary

Equity Residential and AvalonBay have agreed to an all-stock merger of equals to combine into a single company. The combined company will operate from dual headquarters in Chicago, IL, and Arlington, VA, and will include more than 180,000 rental apartment homes. Ben Schall, AvalonBay’s CEO, will serve as CEO of the combined company. The companies expect the merger to close in the second half of 2026, subject to customary closing conditions and shareholder approvals. The email stresses cultural continuity, potential organizational changes after closing, and contains standard forward-looking statements and instructions regarding the forthcoming Registration Statement on Form S-4 and Joint Proxy Statement/Prospectus to be filed with the SEC.

Insights

M&A Strategist

Large-scale consolidation of two REITs to form one of the nation’s largest apartment owners.

The transaction combines two established multifamily portfolios into a single entity described as exceeding 180,000 apartment homes. The filing excerpt frames the deal as an "all-stock merger of equals" and names Ben Schall as CEO of the combined company.

Key execution risks named in the communication include shareholder approvals, integration complexity, potential transaction costs, and possible litigation. Closing timing is conditional; the companies expect completion in the second half of 2026. Future SEC filings (Form S-4 and Joint Proxy Statement/Prospectus) will provide definitive terms and governance details.

HR & Integration Lead

Leadership and organizational changes are signaled with a commitment to cultural continuity and phased integration.

The internal message emphasizes retaining core values and commits to transparent employee communications while noting that team organization and roles will be evaluated after closing. Management indicates some changes may occur quickly, while others will take longer.

Employees are informed that the current Equity Residential CEO will not continue post-close. Human-capital risks include retention of key personnel and operational disruptions during integration; detailed plans and timelines are not included in the excerpt.

Key Figures

Apartment homes combined: 180,000 rental apartment homes Expected closing: second half of 2026 Named CEO: Ben Schall +1 more

4 metrics

Apartment homes combined 180,000 rental apartment homes Combined company scale as stated in the employee email

Expected closing second half of 2026 Merger expected completion timing as stated

Named CEO Ben Schall Will serve as CEO of the combined company

Registration filing Form S-4 Equity Residential intends to file the Registration Statement on Form S-4

Key Terms

merger of equals, Registration Statement on Form S-4, Joint Proxy Statement/Prospectus

3 terms

merger of equals financial

"agreed to combine with AvalonBay in an all-stock merger of equals"

A merger of equals is when two companies of similar size and value combine into a single business with shared ownership and leadership, rather than one company buying the other. Investors care because it reshuffles who owns and controls the combined company, aims to cut duplicate costs and strengthen market position, but also brings integration risks that can affect future profits and each company’s stock value.

Registration Statement on Form S-4 regulatory

"intend to file with the SEC a registration statement on Form S-4"

A registration statement on Form S-4 is a formal filing with the U.S. Securities and Exchange Commission used when a company issues shares or other securities as part of a merger, acquisition, exchange offer or similar corporate deal. It bundles the transaction terms, financial statements, risk factors and shareholder vote materials so investors can assess the deal; think of it as a detailed prospectus or buyer’s packet that explains what you would own and how the deal could change your stake.

Joint Proxy Statement/Prospectus regulatory

"a joint proxy statement of Equity Residential and AvalonBay that also constitutes a prospectus"

A joint proxy statement/prospectus is a single, combined document that both asks shareholders to vote on a proposed transaction and provides the detailed information required when new securities are being offered. Think of it as a combined ballot and product brochure that explains the deal, the companies’ finances, key risks and how ownership will change. Investors rely on it to understand the terms, evaluate risks and make informed voting and investment decisions.

Filed by Equity Residential

ERP Operating Limited Partnership

(Commission File Nos.: 001-12252

000-24920)

Pursuant to Rule 425 under the Securities Act of 1933, as amended

and deemed filed pursuant to Rule 14a-12

under the Securities Exchange Act of 1934

Subject Company: AvalonBay Communities, Inc.

(Commission File No.: 001-12672)

Date: May 21, 2026

All-Employee Email

The below is an email sent to employees of Equity Residential on May 21, 2026 regarding the pending merger of equals between Equity Residential and AvalonBay Communities, Inc. (“AvalonBay”).

To: Mark Parrell

From: Mark Parrell

Bcc: All Employees

Subject: Building the Future Together

Confidential / Do Not Forward Outside Equity Residential

Today marks the beginning of an important new chapter for Equity Residential. We have just announced that Equity Residential has agreed to combine with AvalonBay in an all-stock merger of equals.

By bringing together the strengths of two respected rental housing companies, each with more than 30 years of experience, we have an opportunity to build an even stronger future for our residents, employees, communities, and business.

Together, Equity Residential and AvalonBay will become one of the nation’s leading providers of rental housing, with more than 180,000 rental apartment homes and a strong pipeline of communities under development.

Ben Schall, AvalonBay’s current CEO, will serve as CEO of the combined company. The combined company will have dual headquarters in Chicago, IL, and Arlington, VA. The merger is expected to be completed in the second half of 2026, subject to customary closing conditions, including shareholder approval from both companies.

Why We’re Evolving

Since our founding in 1961, Equity Residential has grown from a single apartment management company into one of the nation’s leading apartment companies by continually evolving, innovating, and focusing on the communities where people most want to live and work. Throughout that growth, what has remained constant is our culture — grounded in our 10 Ways to Be a Winner and the values of optimism, high standards, respect, and collaboration that continue to define who we are today.

Our industry is changing quickly.

Resident expectations continue to grow. Technology is reshaping how work gets done. Investor expectations have changed, and businesses must be able to move faster, operate more efficiently, and adapt to change.

By bringing Equity Residential and AvalonBay together, we have an opportunity to strengthen how we work across the organization while building on the strong foundation both companies already have in place.

The new company will have amazing and unrivaled resources to advance our business and our people. This transformation is about accelerating growth, but it’s also about creating a more connected, capable, and future-ready organization, one that is better positioned to serve residents, support employees, and continue investing in our communities for the long term.

What Will Stay the Same

While parts of the organization may evolve over time, our core commitments will not change.

We remain committed to:

• Delivering great experiences for residents and terrific financial results for our investors

• Supporting our employees and teams

• Investing in our communities

• Operating with a long-term mindset

Both Equity Residential and AvalonBay have a strong history of community investment and long-term ownership, and that approach will continue to guide us moving forward.

What Employees Should Expect

We also want to be transparent: not every future decision has been finalized.

As we continue planning for the future, we will evaluate how teams are organized, how work gets done, and where we can create greater clarity, consistency, and efficiency across the organization.

Some changes may happen quickly after closing, while others will take place over time.

Throughout this process, we are committed to communicating openly, sharing updates as decisions are made, and supporting employees through the transition.

Moving Forward Together

This transformation is about building a stronger future together.

By combining the strengths of Equity Residential and AvalonBay, we have an opportunity to create a company that is more connected, more innovative, and better prepared for the future, while continuing to deliver great experiences for residents and meaningful opportunities for employees.

We know there is still work ahead, and we are excited about what we can build together.

It has been the greatest honor of my professional life to serve as your CEO over the past eight years and to spend the last 27 years as part of the Equity Residential family. You are, without question, the best team in the business, and I know you will bring your talent, passion, and commitment to building a new combined company that will help shape the future of our industry.

While I will not be joining you on this next chapter, I hope you will embrace the opportunity ahead with optimism and confidence. As our founder, Sam Zell, often said, “Go for greatness.”

Cautionary Statement Regarding Forward-Looking Statements

This communication contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended, which are based on current expectations, estimates and projections about the industry and markets in which Equity Residential and AvalonBay Communities, Inc. (“AvalonBay”) operate, as well as beliefs and assumptions of Equity Residential and AvalonBay. Words such as “anticipate,” “become,” “believe,” “could,” “estimate,” “expect,” “forecast,” “intend,” “may,” “outlook,” “plan,” “potential,” “possible,” “predict,” “project,” “target,” “seek,” “shall,” “should,” “will,” or “would,” including variations of such words and similar expressions, are intended to identify forward-looking statements. All statements that address operating performance, events or developments that Equity Residential or AvalonBay expects or

anticipates will occur in the future are forward-looking statements, including statements relating to any possible transaction between Equity Residential and AvalonBay, multifamily market conditions, development, redevelopment, acquisition or disposition activity, general conditions in the geographic areas where Equity Residential and AvalonBay operate and Equity Residential’s and AvalonBay’s respective debt, capital structure and financial position. Such forward-looking statements are not guarantees of future performance and involve known and unknown risks, uncertainties, assumptions and other factors that are difficult to predict and may cause the actual results to differ materially from future results expressed or implied by such forward-looking statements.

Important factors, risks and uncertainties that could cause actual results to differ materially from such plans, estimates or expectations include but are not limited to: (i) the parties’ ability to complete the proposed transaction on the proposed terms or on the anticipated timeline, or at all, including risks and uncertainties related to Equity Residential’s and AvalonBay’s ability to obtain the required respective shareholder approval, and the parties’ ability to satisfy the other conditions to consummating the proposed transaction; (ii) the inability to realize the anticipated benefits of the proposed transaction, including as a result of delay in completing the proposed transaction; (iii) the risk that Equity Residential’s and AvalonBay’s businesses will not be integrated successfully or that such integration may be more difficult, time-consuming or costly than expected; (iv) significant transaction costs and/or unknown or inestimable liabilities; (v) potential litigation relating to the proposed transaction that could be instituted against Equity Residential, AvalonBay or their trustees, directors, managers or officers, including resulting expense or delay and the effects of any outcomes related thereto; (vi) the risk that disruptions from the proposed transaction, including diverting the attention of Equity Residential and AvalonBay management from ongoing business operations, will harm Equity Residential’s and AvalonBay’s businesses during the pendency of the proposed transaction or otherwise; (vii) certain restrictions during the pendency of the business combination that may impact Equity Residential’s and AvalonBay’s ability to pursue certain business opportunities or strategic transactions; (viii) the possibility that the business combination may be more expensive to complete than anticipated, including as a result of unexpected factors or events; (ix) the occurrence of any event, change or other circumstance that could give rise to the termination of the merger agreement, including in circumstances requiring Equity Residential or AvalonBay to pay a termination fee; (x) the effect of the announcement of the proposed transaction on the ability of Equity Residential and AvalonBay to operate their respective businesses and retain and hire key personnel, and to maintain favorable business relationships; (xi) risks related to the market value of Equity Residential common shares to be issued in the proposed transaction; (xii) other risks related to the completion of the proposed transaction and actions related thereto; (xiii) potential business uncertainty, including changes to existing business relationships, during the pendency of the business combination or otherwise that could affect Equity Residential’s or AvalonBay’s financial performance; (xiv) other risks related to the completion of the proposed transaction and actions related thereto; (xv) legislative, regulatory and economic developments, including the level of new multifamily communities construction and development, government regulations and competition; (xvi) unpredictability and severity of local, regional, national and international economic, political and catastrophic climates, conditions and events, including but not limited to acts of terrorism, outbreaks of war or hostilities or pandemics, as well as management’s response to any of the aforementioned factors; (xvii) changes in global financial markets, interest rates and foreign currency exchange rates; (xviii) increased or unanticipated competition affecting Equity Residential’s and AvalonBay’s properties; (xix) risks associated with acquisitions, dispositions, development and redevelopment of properties; (xx) increased costs of labor and construction material; (xxi) maintenance of Real Estate Investment Trust status, tax structuring and changes in income tax laws and rates; (xxii) environmental uncertainties, including risks of natural disasters; (xxiii) those risks and uncertainties set forth in Equity Residential’s and AvalonBay’s Annual Reports on Form 10-K for the year ended December 31, 2025 under the headings “Forward-Looking Statements” and “Risk Factors,” as such risk factors may be amended, supplemented or superseded from time to time by other reports filed by Equity Residential or AvalonBay, as the case may be, with the Securities and Exchange Commission (the “SEC”) from time to time, which are available via the SEC’s website at www.sec.gov; and (xxiv) those risks that will be described in the Registration Statement and Joint Proxy Statement/Prospectus (each as defined below) that will be filed with the SEC in connection with the proposed transaction and available from the sources indicated below. There can be no assurance that the proposed transaction will be completed, or if it is completed, that it will close within the anticipated time period. These factors should not be construed as exhaustive and should be read in conjunction with the other forward-looking statements. Forward-looking statements relate only to events as of the date on which the statements are made. Neither Equity Residential nor AvalonBay undertakes any obligation to publicly update or review any forward-looking statement except as required by law, whether as a result of new information, future developments or otherwise. If one or more of these or other risks or uncertainties materialize, or if Equity Residential’s and AvalonBay’s underlying assumptions prove to be incorrect, Equity Residential’s, AvalonBay’s and the combined company’s actual results may vary materially from what Equity Residential or AvalonBay may have expressed or implied by these forward-looking statements. Equity

Residential and AvalonBay caution not to place undue reliance on any of Equity Residential’s or AvalonBay’s forward-looking statements. Furthermore, new risks and uncertainties arise from time to time, and it is impossible for us to predict those events or how they may affect Equity Residential or AvalonBay.

No Offer or Solicitation

This communication is for informational purposes only and is not intended to, and shall not, constitute an offer to sell or the solicitation of an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval, nor shall there be any offer, solicitation or sale of securities in any jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act.

Important Additional Information and Where to Find It

In connection with the proposed transaction between Equity Residential and AvalonBay, Equity Residential intends to file with the SEC a registration statement on Form S-4 (the “Registration Statement”) that will include a joint proxy statement of Equity Residential and AvalonBay that also constitutes a prospectus of Equity Residential (the “Joint Proxy Statement/Prospectus”). A definitive Joint Proxy Statement/Prospectus will be mailed to Equity Residential’s shareholders and AvalonBay’s stockholders seeking their respective approval of the proposed transaction and other related matters. Each of Equity Residential and AvalonBay may also file other relevant documents with the SEC regarding the proposed transaction. This communication is not a substitute for the Registration Statement, Joint Proxy Statement/Prospectus or any other document that Equity Residential or AvalonBay (as applicable) may file with the SEC in connection with the proposed transaction. BEFORE MAKING ANY VOTING OR INVESTMENT DECISION, INVESTORS AND SECURITY HOLDERS OF EQUITY RESIDENTIAL AND AVALONBAY ARE URGED TO READ CAREFULLY AND IN THEIR ENTIRETY THE REGISTRATION STATEMENT, THE JOINT PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS THAT ARE FILED OR WILL BE FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THESE DOCUMENTS WHEN THEY BECOME AVAILABLE WITH THE SEC BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND RELATED MATTERS. Investors and security holders will be able to obtain free copies of the Registration Statement and the Joint Proxy Statement/Prospectus (when they become available) and other documents filed with the SEC by Equity Residential and AvalonBay, which contain important information, through the website maintained by the SEC at www.sec.gov. The documents filed by Equity Residential with the SEC may be obtained free of charge by accessing “Filings – SEC Filings” in the “Investor” section of Equity Residential’s website at www.equityapartments.com, by writing to Equity Residential – Investor Relations, Two North Riverside Plaza, Suite 500, Chicago, Illinois 60606, by telephone at 1-888-879-6356 or by email at investorrelations@eqr.com. The documents filed by AvalonBay with the SEC may be obtained free of charge by accessing the “Investors” section of AvalonBay’s website at www.avalonbay.com or by writing to AvalonBay, 4040 Wilson Blvd., Suite 1000, Arlington, Virginia 22203, Attention: Corporate Secretary (Legal Department) or by email at investor_relations@avalonbay.com.

Participants in the Solicitation

Equity Residential, AvalonBay, and certain of their respective trustees, directors and executive officers may be deemed to be participants in the solicitation of proxies from Equity Residential’s and AvalonBay’s shareholders in respect of the proposed transaction. Information about the directors and executive officers of AvalonBay, including a description of their direct or indirect interests, by security holdings or otherwise, is set forth in AvalonBay’s proxy statement for its 2026 Annual Meeting of Stockholders under the headings “Director Nominees,” “Transactions with Related Persons, Promoters and Certain Control Persons,” “Director Compensation,” “Director Compensation Table,” “Compensation Discussion and Analysis,” “Executive Compensation Tables” and “Officers, Stock Ownership and Other Information,” which was filed with the SEC on April 6, 2026, and in AvalonBay’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, which was filed with the SEC on February 27, 2026. Information about the trustees and executive officers of Equity Residential, including a description of their direct or indirect interests, by security holdings or otherwise, is set forth in Equity Residential’s proxy statement for its 2026 Annual Meeting of Shareholders under the headings “Biographical Information and Qualifications of Trustees,” “Biographical Information of Executives,” “Common Share Ownership of Trustees and Executives,” “Compensation Discussion and Analysis,” “Executive Compensation” and “Trustee Compensation,” which was filed with the SEC on April 14, 2026, and in Equity Residential’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, which was filed with the SEC on February 13, 2026. To the

extent holdings of Equity Residential’s securities by its trustees or executive officers have changed since the amounts set forth in Equity Residential’s definitive proxy statement for its 2026 Annual Meeting of Shareholders or the holdings of AvalonBay’s securities by its directors or executive officers have changed since the amounts set forth in AvalonBay’s definitive proxy statement for its 2026 Annual Meeting of Stockholders, such changes have been or will be reflected on an Initial Statement of Beneficial Ownership of Securities on Form 3, Statement of Changes in Beneficial Ownership on Form 4, or Annual Statement of Changes in Beneficial Ownership on Form 5, in each case filed with the SEC and available on the SEC’s website at www.sec.gov. Other information regarding the participants in the proxy solicitations and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the Registration Statement, the Joint Proxy Statement/Prospectus and other relevant materials to be filed with the SEC regarding the proposed transaction when such materials become available. Investors and security holders should read the Registration Statement and the Joint Proxy Statement/Prospectus carefully when they become available before making any voting or investment decisions. Investors may obtain free copies of these documents from Equity Residential or AvalonBay using the sources indicated above.

FAQ

What did Equity Residential and AvalonBay announce (AVB)?

They announced an all-stock merger of equals to form a combined company with more than 180,000 rental apartment homes. The combined company will have dual headquarters in Chicago, IL, and Arlington, VA.

Who will lead the combined company after the merger?

Ben Schall, AvalonBay’s current CEO, will serve as CEO of the combined company. The current Equity Residential CEO stated he will not continue in the CEO role after closing.

When is the merger expected to close?

The companies expect the merger to be completed in the second half of 2026, subject to customary closing conditions and shareholder approvals from both companies.

What SEC filings will be available about the transaction?

Equity Residential intends to file a Registration Statement on Form S-4 that will include a Joint Proxy Statement/Prospectus. These materials will contain detailed terms and will be mailed to shareholders when available.