Sec Form 4 Filing - Mahmood Nabeel @ UNITED SECURITY BANCSHARES - 2026-04-01

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person Mahmood Nabeel 2. Issuer Name and Ticker or Trading Symbol UNITED SECURITY BANCSHARES [ UBFO] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 2126 INYO STREET 3. Date of Earliest Transaction (MM/DD/YY) 04/01/2026 (Street) FRESNO, CA93721 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 04/01/2026 D 23,556.883 D $ 10.51 ( 1 ) 0 D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Stock Options $ 11.05 04/01/2026 D 15,000 12/19/2018 12/19/2027 Common Stock 15,000 ( 2 ) 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Mahmood Nabeel 2126 INYO STREET FRESNO, CA93721 X Signatures /s/ Nabeel Mahmood 04/01/2026 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Disposed of pursuant to the Agreement and Plan of Merger, dated as of December 16, 2025 (the "Merger Agreement"), by and between Community West Bancshares ("Community West") and United Security Bancshares (the "Company"), providing for the Company to merge (the "Merger") with and into Community West with Community West being the surviving entity. The Merger became effective at 12:01 a.m. on April 1, 2026 (the "Effective Time"), at which time (i) each share of Company common stock, other than excluded shares and dissenting shares, was converted into the right to receive 0.4520 of a share of common stock of Community West (the "Merger Consideration"); each outstanding unvested Company restricted stock award automatically vested in full and became entitled to the Merger Consideration. ( 2 )Pursuant to the Merger Agreement, at the effective time of the merger, each of the reporting person's stock options were converted into the right to receive the amount, if any, by which the option's price exceeded $10.29 (20 day VWAP ending 3/27/2026).

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.