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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

____________________

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

____________________

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☐	Definitive Proxy Statement
☒	Definitive Additional Materials
☐	Soliciting Material under 240.14a-12

Smith Micro Software, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

☒	No fee required
☐	Fee paid previously with preliminary materials
☐	Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

Step 1: Go to www.envisionreports.com/SMSI. Step 2: Click on Cast Your Vote or Request Materials. Step 3: Follow the instructions on the screen to log in. www.envisionreports.com/SMSI Online Go to www.envisionreports.com/SMSI or scan the QR code — login details are located in the shaded bar below. Stockholder Meeting Notice 044Z0A Important Notice Regarding the Availability of Proxy Materials for the Smith Micro Software, Inc. Annual Stockholder Meeting to be Held on June 3, 2025 Under Securities and Exchange Commission rules, you are receiving this notice that the proxy materials for the annual stockholders meeting are available on the Internet. Follow the instructions below to view the materials and vote online or request a copy. The items to be voted on and location of the annual meeting are on the reverse side. Your vote is important! This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. We encourage you to access and review all of the important information contained in the proxy materials before voting. The 2024 Annual Report and the Proxy Statement for the 2025 Annual Meeting of Stockholders are available at: Obtaining a Copy of the Proxy Materials – If you want to receive a copy of the proxy materials, you must request one. There is no charge to you for requesting a copy. Please make your request as instructed on the reverse side on or before May 23, 2025 to facilitate timely delivery. 2 N O T Easy Online Access — View your proxy materials and vote. When you go online, you can also help the environment by consenting to receive electronic delivery of future materials. The Sample Company Step 4: Make your selections as instructed on each screen for your delivery preferences. Step 5: Vote your shares. MMMMMMMMMMMM M M M M M M M M M 0 0 0 0 0 1 MR A SAMPLE DESIGNATION (IF ANY) ADD 1 ADD 2 ADD 3 ADD 4 ADD 5 ADD 6 ENDORSEMENT_LINE______________ SACKPACK_____________ 1234 5678 9012 345 C 1234567890 C O Y MMMMMMM

Here’s how to order a copy of the proxy materials and select delivery preferences: Current and future delivery requests can be submitted using the options below. If you request an email copy, you will receive an email with a link to the current meeting materials. PLEASE NOTE: You must use the number in the shaded bar on the reverse side when requesting a copy of the proxy materials. — Internet – Go to www.envisionreports.com/SMSI. Click Cast Your Vote or Request Materials. — Phone – Call us free of charge at 1-866-641-4276. — Email – Send an email to investorvote@computershare.com with “Proxy Materials Smith Micro Software, Inc.” in the subject line. Include your full name and address, plus the number located in the shaded bar on the reverse side, and state that you want a paper copy of the meeting materials. To facilitate timely delivery, all requests for a paper copy of proxy materials must be received by May 23, 2025. The 2025 Annual Meeting of Stockholders of Smith Micro Software, Inc. will be held on June 3, 2025, 11:00 a.m. Eastern Time, virtually via the internet at meetnow.global/MHZWG2G. To access the virtual meeting, you must have the information that is printed in the shaded bar located on the reverse side of this form. Proposals to be voted on at the meeting are listed below along with the Board of Directors’ recommendations. The Board of Directors recommends a vote FOR all nominees and FOR Proposals 2, 3, 4 and 5: 1. Election of two (2) Directors to serve a three-year term ending at the 2028 Annual Meeting of Stockholders or until their successors are duly elected and qualified: 01 - Andrew Arno 02 - Samuel Gulko 2. Non-binding advisory vote to approve the compensation of named executive officers. 3. Ratification of the appointment of SingerLewak LLP as the independent registered public accounting firm of Smith Micro Software, Inc. for the fiscal year ending December 31, 2025. 4. Approval of an amendment to the Smith Micro Software, Inc. Amended and Restated Omnibus Equity Incentive Plan. 5. Approval of an amendment to the Smith Micro Software, Inc. Amended and Restated Employee Stock Purchase Plan. PLEASE NOTE – YOU CANNOT VOTE BY RETURNING THIS NOTICE. To vote your shares you must go online or request a paper copy of the proxy materials to receive a proxy card. If you wish to attend and vote at the meeting, please bring this notice with you. Stockholder Meeting Notice