Business Combination Prospectus (Form 425)

Filed by Steelcase Inc.

pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

under the Securities Exchange Act of 1934

Subject company: Steelcase Inc.

Commission file number: 001-13873

The following is an email sent to Steelcase Inc. employees on September 3, 2025.

INCENTIVE MAIL

Author: Donna Flynn

Subject: What to Expect Regarding Incentive Programs

Date: September 3, 2025

Hello,

Earlier today, Sara shared information about our bonus programs, and now we're providing details on incentive programs for those who participate or are eligible. Details regarding these programs and how they will work now and following the completion of the HNI acquisition are below:

Management Incentive Plan (MIP)

You'll be eligible for a pro-rated bonus from March 1, 2025, through closing, based on one or both of the MIP performance measures below:

Bonuses will be paid within 30 days of closing.

Steelcase Cash-Based Awards

If you have unvested awards at the time of closing, performance conditions will be deemed achieved at:

All other terms of your original awards remain unchanged.

Restoration Retirement Plan (RRP)

If you have a balance in the RRP, it will be paid in a single lump sum within 60 days of closing. If you're already receiving payments, your annual installment schedule will continue.

Deferred Compensation Plan (DCP)

Following the closing, HNI will assume the deferred compensation plan and continue distributions per your elections.

Restricted Stock Units (RSUs)

Unvested RSUs will convert into a mix of HNI RSUs and a cash award (with interest), based on the shareholder transaction terms:

Converted awards will retain the same vesting and other terms and conditions and the cash award will earn interest through vesting.

While not anticipated, if the closing date changes, the amounts or distribution dates may be subject to revision. The transaction is currently expected to close by the end of calendar year 2025, subject to customary closing conditions.

We understand that transitions like these can bring questions and uncertainty. Your continued leadership and contributions are appreciated. As we navigate this next chapter together, your commitment to delivering value and supporting our strategic goals is more important than ever. Thank you for your dedication, resilience, and partnership during this time of change. If you have questions, please reach out to Nancy Kocsis or Courtney Rapson.

You can also visit the HNI + Steelcase page on Spark.

UPDATED FAQs

Will I receive an annual bonus payment at the closing of the HNI transaction?

Steelcase will continue to operate under a business-as-usual approach. It's essential that we remain committed to executing our strategic initiatives and achieving our FY26 Plan. Following the closing of the transaction, we will pay a bonus multiple of 1.10 to eligible employees. The bonus will be prorated for the period from March 1, 2025 through the closing of the transaction and will be paid within 30 days after closing. For bonus-eligible employees in our affiliate businesses, the bonus plans will remain the same through closing, and we will share more information on pro rata payouts and timing at closing.

While the structure of annual bonuses following the closing has not yet been finalized, HNI is expected to maintain similar short-term and long-term incentive compensation opportunities following the closing. We intend to work closely with HNI to determine the structure of future bonuses, including any portion of the current fiscal year following the closing, and will share additional information as it becomes available.

What happens with my 401(k) (U.S. only)?

There is no change to your 401(k) at this time. HNI does have the option to move Steelcase employees on to the HNI 401(k) plan after closing and is considering alternatives, but HNI intends to provide substantially comparable 401(k) plan benefits and investment options regardless of approach.

Steelcase will continue to provide employer matching contributions to 401(k) accounts through the date of closing, and HNI will provide a similar matching program following the closing. For the current plan year, Steelcase will make a prorated profit-sharing contribution of 5.5% through the closing date for FY26 for eligible U.S. employees. This will be posted to your Empower account within 60 days after closing and is based on your eligible wages from the plan year, which runs from March 1, 2025 to closing.

If the Steelcase 401(k) plan is terminated after closing, any unvested portion of your 401(k) account will become fully vested prior to plan termination. If the Steelcase 401(k) plan is not terminated, any unvested portion of your 401(k) account will continue to vest in accordance with its current terms.

Forward-Looking Statements

This communication contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934 and Section 27A of the Securities Act of 1933, which involve risks and uncertainties. Any statements about HNI's, Steelcase's or the combined company's plans, objectives, expectations, strategies, beliefs, or future performance or events and any other statements to the extent they are not statements of historical fact are forward-looking statements. Words, phrases or expressions such as "anticipate," "believe," "could," "confident," "continue," "estimate," "expect," "forecast," "hope," "intend," "likely," "may," "might," "objective," "plan," "possible," "potential," "predict," "project", "target," "trend" and similar words, phrases or expressions are intended to identify forward looking statements but are not the exclusive means of identifying such statements. Forward-looking statements are based on information available and assumptions made at the time the statements are made. Forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from those expressed in or implied by the forward-looking statements. Forward-looking statements in this communication include, but are not limited to, statements about the benefits of the transaction between HNI and Steelcase (the "Transaction"), including future financial and operating results, the combined company's plans, objectives, expectations and intentions, and other statements that are not historical facts.

The following Transaction-related factors, among others, could cause actual results to differ materially from those expressed in or implied by forward-looking statements: the occurrence of any event, change, or other circumstance that could give rise to the right of one or both of the parties to terminate the definitive merger agreement between HNI and Steelcase; the outcome of any legal proceedings that may be instituted against HNI or Steelcase; the possibility that the Transaction does not close when expected or at all because required regulatory, shareholder, or other approvals and other conditions to closing are not received or satisfied on a timely basis or at all (and the risk that seeking or obtaining such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the Transaction); the risk that the benefits from the Transaction may not be fully realized or may take longer to realize than expected, including as a result of changes in, or problems arising from, general economic and market conditions, interest and exchange rates, monetary policy, trade policy (including tariff levels), laws and regulations and their enforcement, and the degree of competition in the geographic and business areas in which HNI and Steelcase operate; any failure to promptly and effectively integrate the businesses of HNI and Steelcase; the possibility that the Transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; reputational risk and potential adverse reactions of HNI's or Steelcase's customers, employees or other business partners, including those resulting from the announcement, pendency or completion of the Transaction; the dilution caused by HNI's issuance of additional shares of its capital stock in connection with the Transaction; and the diversion of management's attention and time to the Transaction from ongoing business operations and opportunities.

Additional important factors relating to Steelcase that could cause actual results to differ materially from those in forward-looking statements include, but are not limited to, competitive and general economic conditions domestically and internationally; acts of terrorism, war, governmental action, natural disasters, pandemics and other Force Majeure events; cyberattacks; changes in the legal and regulatory environment; changes in raw material, commodity and other input costs; currency fluctuations; changes in customer demand; and the other risks and contingencies detailed in Steelcase's most recent Annual Report on Form 10-K and its other filings with the U.S. Securities and Exchange Commission (the "SEC").

Additional important factors relating to HNI that could cause actual results to differ materially from those in forward-looking statements include, but are not limited to, HNI's ultimate realization of the anticipated benefits of the acquisition of Kimball International; disruptions in the global supply chain; the effects of prolonged periods of inflation and rising interest rates; labor shortages; the levels of office furniture needs and housing starts; overall demand for HNI's products; general economic and market conditions in the United States and internationally; industry and competitive conditions; the consolidation and concentration of HNI's customers; HNI's reliance on its network of independent dealers; change in trade policy, including with respect to tariff levels; changes in raw material, component, or commodity pricing; market acceptance and demand for HNI's new products; changing legal, regulatory, environmental, and healthcare conditions; the risks associated with international operations; the potential impact of product defects; the various restrictions on HNI's financing activities; an inability to protect HNI's intellectual property; cybersecurity threats, including those posed by potential ransomware attacks; impacts of tax legislation; and force majeure events outside HNI's control, including those that may result from the effects of climate change, a description of which risks and uncertainties and additional risks and uncertainties can be found in HNI's most recent Annual Report on Form 10-K and its other filings with the SEC.

These factors are not necessarily all of the factors that could cause HNI's, Steelcase's or the combined company's actual results, performance, or achievements to differ materially from those expressed in or implied by any forward-looking statements. Other unknown or unpredictable factors also could harm HNI's, Steelcase's or the combined company's results.

All forward-looking statements attributable to HNI, Steelcase, or the combined company, or persons acting on HNI's or Steelcase's behalf, are expressly qualified in their entirety by the cautionary statements set forth above. Forward-looking statements speak only as of the date they are made, and HNI and Steelcase do not undertake or assume any obligation to update publicly any of these statements to reflect actual results, new information or future events, changes in assumptions, or changes in other factors affecting forward-looking statements, except to the extent required by applicable law. If HNI or Steelcase updates one or more forward-looking statements, no inference should be drawn that HNI or Steelcase will make additional updates with respect to those or other forward-looking statements. Further information regarding HNI, Steelcase and factors that could affect the forward-looking statements contained herein can be found in HNI's Annual Report on Form 10-K, its Quarterly Reports on Form 10-Q, and its other filings with the SEC, and in Steelcase's Annual Report on Form 10-K, its Quarterly Reports on Form 10-Q, and its other filings with the SEC.

No Offer or Solicitation

This communication is not an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any 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 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 of 1933, as amended.

Important Information and Where to Find It

In connection with the Transaction, HNI will file with the SEC a Registration Statement on Form S-4 to register the shares of HNI common stock to be issued in connection with the Transaction. The Registration Statement will include a joint proxy statement of HNI and Steelcase that also constitutes a prospectus of HNI. The definitive joint proxy statement/prospectus will be sent to the shareholders of each of HNI and Steelcase.

INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE REGISTRATION STATEMENT ON FORM S-4 AND THE JOINT PROXY STATEMENT/PROSPECTUS WHEN THEY BECOME AVAILABLE, AS WELL AS ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC IN CONNECTION WITH THE TRANSACTION OR INCORPORATED BY REFERENCE INTO THE JOINT PROXY STATEMENT/PROSPECTUS, BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION REGARDING HNI, STEELCASE, THE TRANSACTION AND RELATED MATTERS.

Investors and security holders may obtain free copies of these documents and other documents filed with the SEC by HNI or Steelcase through the website maintained by the SEC at http://www.sec.gov or from HNI at its website, www.hnicorp.com, or from Steelcase at its website, www.steelcase.com (information included on or accessible through either of HNI's or Steelcase's website is not incorporated by reference into this communication).

Participants in the Solicitation

HNI, Steelcase, their respective directors and certain of their respective executive officers may be deemed to be participants in the solicitation of proxies in connection with the Transaction under the rules of the SEC. Information about the interests of the directors and executive officers of HNI and Steelcase and other persons who may be deemed to be participants in the solicitation of proxies in connection with the Transaction and a description of their direct and indirect interests, by security holdings or otherwise, will be included in the joint proxy statement/prospectus related to the Transaction, which will be filed with the SEC. Information about the directors and executive officers of HNI and their ownership of HNI common stock is set forth in the definitive proxy statement for HNI's 2025 Annual Meeting of Shareholders, filed with the SEC on March 11, 2025; in Table I (Information about our Executive Officers) at the end of Part I of HNI's Annual Report on Form 10-K for the fiscal year ended December 28, 2024, filed with the SEC on February 25, 2025; in HNI's Current Report on Form 8-K filed with the SEC on June 20, 2025; in the Form 3 and Form 4 statements of beneficial ownership and statements of changes in beneficial ownership filed with the SEC by HNI's directors and executive officers; and in other documents filed by HNI with the SEC. Information about the directors and executive officers of Steelcase and their ownership of Steelcase common stock can be found in Steelcase's definitive proxy statement in connection with its 2025 Annual Meeting of Shareholders, filed with the SEC on May 28, 2025; under the heading "Supplementary Item. Information About Our Executive Officers" in Steelcase's Annual Report on Form 10-K for the fiscal year ended February 28, 2025, filed with the SEC on April 18, 2025; in Steelcase's Amendment No. 1 to Current Report on Form 8-K/A filed with the SEC on July 11, 2025; in the Form 3 and Form 4 statements of beneficial ownership and statements of changes in beneficial ownership filed with the SEC by Steelcase's directors and executive officers; and in other documents filed by Steelcase with the SEC. Free copies of the documents referenced in this paragraph may be obtained as described above under the heading "Important Information and Where to Find It."