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Approximate date of commencement of proposed sale to the public: Not applicable. Removal from registration of securities that were not sold pursuant to the above-referenced registration statement.

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


Large accelerated filer ☒			Accelerated filer ☐			Non‑accelerated filer ☐			Smaller reporting company ☐ Emerging growth company ☐

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This Post-Effective Amendment to the following registration statement on Form S-3ASR (the “Registration Statement”) is being filed by Pinnacle Financial Partners, Inc., a Tennessee corporation (“Legacy Pinnacle”) to terminate all offerings under the Registration Statement and to deregister any and all securities of Legacy Pinnacle registered but unsold as of the date hereof thereunder:

1.Registration Statement on Form S-3ASR, File No. 333-272565, filed with the Securities and Exchange Commission (the “Commission”) on June 9, 2023, registering an unspecified amount of debt securities, preferred stock, depositary shares, common stock, warrants, units and stock purchase contracts.

On January 1, 2026, pursuant to the Agreement and Plan of Merger, dated as of July 24, 2025, by and among Legacy Pinnacle, Synovus Financial Corp. (“Synovus”) and Pinnacle Financial Partners, Inc. (f/k/a Steel Newco Inc.) (“Newco”) (the “Merger Agreement”), Legacy Pinnacle and Synovus each simultaneously merged with and into Newco (such mergers, collectively, the “Merger”), with Newco continuing as the surviving corporation in the Merger and named Pinnacle Financial Partners, Inc.

In connection with the Merger, Legacy Pinnacle has terminated all offerings of Legacy Pinnacle’s securities pursuant to the Registration Statement. Accordingly, pursuant to the undertakings made by Legacy Pinnacle in the Registration Statement to remove from registration, by means of a post-effective amendment, any of the securities that remain unsold at the termination of the offerings, this Post-Effective Amendment hereby removes from registration all of such securities registered under the Registration Statement that remain unsold as of the date of this Post-Effective Amendment.

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Post-Effective Amendment to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Atlanta, State of Georgia, on the 2nd day of January, 2026.

No other person is required to sign this Post-Effective Amendment to the Registration Statement in reliance upon Rule 478 under the Securities Act of 1933, as amended.