OPBK · OP Bancorp · Debt

4 No. 2035-1 CUSIP / ISIN: 67109RAA7 OP BANCORP 7.50% FIXED-TO-FLOATING RATE SUBORDINATED NOTE DUE NOVEMBER 15, 2035 1. Subordinated Note. This Subordinated Note is one of an issue of note of OP BANCORP a California corporation (the “Company”) designated as the “7.50% Fixed-to-Floating Rate Subordinated Note due November 15, 2035” (the “Subordinated Note”) issued pursuant to that Subordinated Note Purchase Agreement, dated as of November 7, 2025, by and among the Company and the several purchasers of the Subordinated Note identified on the signature pages thereto (the “Purchase Agreement”). 2. Payment. The Company, for value received, promises to pay to Cede & Co., or its registered assigns, the principal sum of Twenty-Five Million Dollars (U.S.) ($25,000,000.00), plus accrued but unpaid interest on November 15, 2035 (the “Stated Maturity”) and to pay interest thereon (i) from and including November 7, 2025 (the “Issue Date”) to but excluding November 15, 2030 or the earlier redemption date contemplated by Section 4 of this Subordinated Note, at the rate of 7.50% per annum, computed on the basis of a 360-day year consisting of twelve 30-day months and payable semi- annually in arrears on May 15 and November 15 of each year (each payment date, a “Fixed Rate Interest Payment Date”), beginning May 15, 2026, and (ii) from and including November 15, 2030, to but excluding the Stated Maturity or the earlier redemption date contemplated by Section 4 of this Subordinated Note, at the rate per annum, reset quarterly, equal to the Floating Interest Rate (as defined below) determined on the Floating Interest Determination Date (as defined below) of the applicable interest period plus 411 basis points, computed on the basis of a 360-day year and the actual number of days elapsed and payable quarterly in arrears (each quarterly period, a “Floating Rate Period”) on February 15, May 15, August 15, and November 15 of each year (each payment date, a “Floating Rate Interest Payment Date”). Dollar amounts resulting from this calculation shall be rounded to the nearest cent, with one-half cent being rounded up. The term “Floating Interest Determination Date” means the date upon which the Floating Interest Rate is determined by the Calculation Agent (as defined below) pursuant to the Three-Month Term SOFR Conventions (as defined below). Any payment of principal of or interest on this Subordinated Note that would otherwise become due and payable on a day which is not a Business Day shall become due and payable on the next succeeding Business Day, with the same force and effect as if made on the date for payment of such principal or interest, and no interest will accrue in respect of such payment for the period after such day; provided, that in the event that any scheduled Floating Rate Interest Payment Date falls on a day that is not a Business Day and the next succeeding Business Day falls in the next succeeding calendar month, such Floating Rate Interest Payment Date will be accelerated to the immediately preceding Business Day, and, in each such case, the amounts payable on such Business Day will include interest accrued to, but excluding, such Business Day. Dollar amounts resulting from interest calculations will be rounded to the nearest cent, with one half cent being rounded upward. Notwithstanding anything to the contrary, (i) in the event the Three-Month Term SOFR (as defined below) is less than zero, the Three-Month Term SOFR shall be deemed to be zero, and (ii) if a Benchmark Transition Event (as defined below) and its related Benchmark Replacement Date (as defined below) have occurred and the Benchmark Replacement (as defined below) is less than zero, then the Benchmark Replacement shall be deemed to be zero. (a) The Company shall take such actions as are necessary to ensure that from the commencement of the Floating Rate Period for so long as any of the Subordinated Note remain

Issuer evidence: THE INDEBTEDNESS EVIDENCED BY THIS SUBORDINATED NOTE IS SUBORDINATED AND JUNIOR IN RIGHT OF PAYMENT TO SENIOR INDEBTEDNESS (AS DEFINED IN SECTION 3 OF THIS SUBORDINATED NOTE) OF OP BANCORP, A CALIFORNIA CORPORATION (THE “COMPANY”), INCLUDING OBLIGATIONS OF THE COMPANY TO ITS GENERAL CREDITORS AND SECURED CREDITORS, AND IS UNSECURED, AND TO THE OBLIGATIONS OF ITS WHOLLY OWNED SUBSIDIARY, OPEN BANK (“BANK”) TO THE BANK’S DEPOSITORS AND OTHER CREDITORS, SECURED AND UNSECURED.

Supporting evidence: This Subordinated Note is one of an issue of note of OP BANCORP a California corporation (the “Company”) designated as the “7.50% Fixed-to-Floating Rate Subordinated Note due November 15, 2035” (the “Subordinated Note”) issued pursuant to that Subordinated Note Purchase Agreement, dated as of November 7, 2025, by and among the Company and the several purchasers of the Subordinated Note identified on the signature pages thereto (the “Purchase Agreement”).

On November 7, 2025, OP Bancorp (the “Company”), the parent company of Open Bank (the “Bank”), completed a private placement of $25 million principal amount of fixed-to-floating rate subordinated note due 2035 (the “Note”) pursuant to a subordinated note purchase agreement in a private placement (the “Agreement”).

Issuer evidence: On November 7, 2025, OP Bancorp (the “Company”), the parent company of Open Bank (the “Bank”), completed a private placement of $25 million principal amount of fixed-to-floating rate subordinated note due 2035 (the “Note”) pursuant to a subordinated note purchase agreement in a private placement (the “Agreement”).

Supporting evidence: The Note will mature on November 15, 2035. From the original issue date to, but excluding, November 15, 2030, the Note will bear interest at a fixed rate of 7.50% per annum and payable semi-annually in arrears on May 15 and November 15 of each year, beginning May 15, 2026. Thereafter, until maturity or earlier redemption, the Note will bear interest at a floating rate, reset quarterly, equal to the three-month term Secured Overnight Financing Rate (“SOFR”) plus 411 basis points and payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year. The Company may, at its option, redeem the Note, in whole or part, at any time after the fifth anniversary of issuance, subject to any required regulatory approvals. The Note was designed to qualify as Tier 2 capital under applicable capital adequacy regulations. The Company intends to use the net proceeds for general corporate purposes, including, without limitation, strengthening the regulatory capital of the Bank and supporting its growth.

Supporting evidence: On November 7, 2025, OP Bancorp (the “Company”), the parent company of Open Bank (the “Bank”), completed a private placement of $25 million principal amount of fixed-to-floating rate subordinated note due 2035 (the “Note”) pursuant to a subordinated note purchase agreement in a private placement (the “Agreement”).

Supporting evidence: On November 7, 2025, OP Bancorp (the “Company”), the parent company of Open Bank (the “Bank”), completed a private placement of $25 million principal amount of fixed-to-floating rate subordinated note due 2035 (the “Note”) pursuant to a subordinated note purchase agreement in a private placement (the “Agreement”).