Exhibit 5.1

May 26, 2023
	Norton Rose Fulbright US LLP
	2200 Ross Avenue, Suite 3600 Dallas, Texas 75201-7932 United States
	Tel +1 214 855 8000 Fax +1 214 855 8200 nortonrosefulbright.com

Stellar Bancorp, Inc.
9 Greenway Plaza, Suite 110
Houston, Texas 77046

Ladies and Gentlemen:

We have acted as special counsel to Stellar Bancorp, Inc., a Texas corporation (the “Company”), with respect to certain legal matters in connection with the registration under the Securities Act of 1933, as amended (the “Securities Act”), of the offer and sale by the Company from time to time, pursuant to Rule 415 under the Securities Act, of an indeterminate amount of: (i) debt securities of the Company (“Debt Securities”), in one or more series, which may be senior debt securities or subordinated debt securities, and may be convertible into or exchangeable for Preferred Stock or Common Stock (both as defined below); (ii) common stock of the Company, par value $0.01 per share (“Common Stock”); (iii) preferred stock of the Company, par value $0.01 per share (“Preferred Stock,” and together with Common Stock, “Company Stock”), in one or more series, which may be convertible into or exchangeable for Debt Securities or Common Stock; (iv) depositary shares representing fractional interests in shares of Preferred Stock of any series (“Depositary Shares”); (v) warrants to purchase Debt Securities or shares of Company Stock (“Warrants”); (vi) purchase contracts for the purchase or sale of the Company’s Debt Securities, Common Stock or Depositary Shares (“Purchase Contracts”); (vii) rights to purchase Common Stock or other securities that the Company may offer (“Rights”); and (viii) units that include Debt Securities, Common Stock, Preferred Stock, Depositary Shares, Warrants, Purchase Contracts, Rights or any combination thereof (“Units”), and each on terms to be determined at the time of its offering. The Debt Securities, Company Stock, Depositary Shares, Warrants, Purchase Contracts, Rights and Units are collectively referred to herein as the “Securities.”

We also have participated in the preparation of the Prospectus (the “Prospectus”) contained in the Registration Statement on Form S-3 (the “Registration Statement”) to which this letter is an exhibit. The Securities will be offered in amounts, at prices and on terms to be determined in light of market conditions at the time of sale and to be set forth in supplements to the Prospectus (each, a “Prospectus Supplement”) contained in the Registration Statement. Capitalized terms not otherwise defined in this letter shall have the meanings ascribed to them in the Prospectus.

The Debt Securities are to be issued under a senior debt indenture, to be entered into by and between the Company and the trustee named therein (in the case of senior Debt Securities) (the “Senior Indenture”), or the subordinated indenture, between the Company and U.S. Bank Trust Company, National Association, filed as an exhibit to the Registration Statement (in the case of subordinated Debt Securities) (the “Subordinated Indenture” and together with the Senior Indenture, the “Indentures”).

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In rendering the opinions set forth below, we have examined and relied upon: (i) the Registration Statement, including the Prospectus; (ii) the Company’s Second Amended and Restated Certificate of Formation (the “Certificate of Formation”), (iii) Company’s Bylaws (the “Bylaws”); (iv) resolutions of the Board of Directors of the Company relating to the Registration Statement; (v) the Indentures filed as exhibits to the Registration Statement; and (vi) such certificates, statutes and other instruments and documents as we considered appropriate for purposes of the opinions expressed in this letter. In addition, we reviewed such questions of law as we considered appropriate to enable us to render the opinions expressed in this letter. As to matters of fact relevant to the opinions expressed below and as to factual matters arising in connection with our review of corporate documents, records, and other documents and writings, we have made no independent investigation of such facts, and we have relied in certain cases upon certificates and other communications of officers and employees of the Company without further investigation as to the facts set forth in such certificates and communications.

In connection with rendering the opinions expressed in this letter, we have assumed that:

(i)            all information contained in all documents reviewed by us is true and correct;

(ii)           all signatures on all documents examined by us are genuine and each individual who signed any of those documents had legal capacity and authority to do so;

(iii)           all documents submitted to us as originals are authentic, all documents submitted to us as copies conform to the authentic originals of those documents and all documents examined by us are duly authorized, executed and delivered by the parties thereto (other than the Company);

(iv)          the Certificate of Formation and Bylaws will not have been amended in any manner that would affect any legal conclusion set forth in this letter, and any certificate of designations in respect of Preferred Stock will be in conformity therewith and with applicable law;

(v)           the consideration paid for any shares of Company Stock will comply with the Texas Business Organizations Code (the “TBOC”), as applicable, and any successor statute(s);

(vi)          the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective;

(vii)         a Prospectus Supplement will have been prepared and filed with the Securities and Exchange Commission describing the Securities offered thereby;

(viii)       all Securities will be offered and sold in compliance with applicable federal and state securities laws and in the manner specified in the Registration Statement and the applicable Prospectus Supplement;

(ix)          the Board of Directors of the Company or, to the extent permitted by the Texas Business Organizations Code and the Certificate of Formation and Bylaws, a duly constituted and acting committee thereof (such Board of Directors or committee thereof being hereinafter referred to as the “Board”), will have taken all necessary corporate action to authorize the issuance of the Securities and any other Securities issuable on the conversion, exchange, redemption or exercise thereof, and to authorize the terms of the offering and sale of such Securities and related matters;

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(x)            with respect to Securities to be offered through an agent, underwriter or dealer or to or through a market maker, the form, terms and conditions of a definitive purchase, placement, agency, underwriting or similar agreement with respect to any Securities or, with respect to Securities to be sold by the Company directly to investors in privately negotiated transactions, the form, terms and conditions of such agreement with respect to such Securities, will have been duly authorized and validly executed and delivered by the parties thereto (other than the Company);

(xi)          in the case of the Debt Securities, (A) the Board will have taken all necessary corporate action to authorize the form, terms, execution, delivery, performance, issuance and sale of any Debt Securities of any series as contemplated by the Registration Statement, the Prospectus Supplement relating to such series of Debt Securities and the Senior Indenture or Subordinated Indenture, as applicable, for such series of Debt Securities and to authorize the execution, delivery and performance of the supplemental indenture or resolution of the Board establishing the form and terms of such series of Debt Securities as contemplated by the Senior Indenture or Subordinated Indenture, as applicable; (B) the Senior Indenture and the Subordinated Indenture, as applicable, will not have been modified or amended (other than by a supplemental indenture or resolution of the Board establishing the form or terms of the Debt Securities of any series); (C) each person signing the Senior Indenture, the Subordinated Indenture and supplemental indenture, if any, will have the legal capacity and authority to do so; and (D) the terms of such Debt Securities will (i) not (x) include any provision that is unenforceable, (y) violate any applicable law or (z) result in a default under or breach of any agreement or instrument binding upon the Company and (ii) comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company;

(xii)          in the case of shares of Common Stock, the Board will have taken all necessary corporate action to approve the issuance of the Common Stock;

(xiii)         in the case of shares of Preferred Stock of any series, the Board will have taken all necessary corporate action to designate and establish the terms of such series and will have caused a certificate of designations with respect to such series to be prepared and filed with the Secretary of State of the State of Texas, and the terms of such series will not violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company and will comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company;

(xiv)        in the case of Depositary Shares, any depositary agreement with respect to the Depositary Shares will have been duly authorized and validly executed and delivered by the parties thereto (other than the Company) and each person signing such depositary agreement will have the legal capacity and authority to do so;

(xv)          in the case of Warrants, (A) the Board will have taken all necessary corporate action to authorize the creation of and the terms of such Warrants and the issuance of the Securities to be issued pursuant thereto and to approve the warrant agreement relating thereto; (B) such warrant agreement will have been duly executed and delivered by the warrant agent thereunder appointed by the Company; (C) each person signing such warrant agreement will have the legal capacity and authority to do so; (D) neither such Warrants nor such warrant agreement will include any provision that is unenforceable, that violates any applicable law or results in a default under or breach of any agreement or instrument binding upon the Company; (E) the terms of such Warrants and such warrant agreement and the issuance and sale of the Warrants will comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company; and (F) such Warrants or certificates representing such Warrants will have been duly executed, countersigned, registered and delivered by the parties thereto (other than the Company) in accordance with the provisions of such warrant agreement;

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(xvi)        at the time of execution, countersignature, issuance and delivery of the Purchase Contracts and Unit agreements, such Purchase Contracts and Unit agreements will have been duly authorized and validly executed and delivered by the parties thereto (other than the Company) and each person signing such Purchase Contracts and Unit agreements will have the legal capacity and authority to do so;

(xvii)       in the case of Rights, (A) the Board will have taken all necessary corporate action to authorize the creation of and the terms of such Rights and the issuance of the Securities to be issued pursuant thereto and to approve the rights or subscription agreement relating thereto; (B) such rights or subscription agreement will have been duly executed and delivered by the rights or subscription agent thereunder appointed by the Company; (C) each person signing such rights or subscription agreement will have the legal capacity and authority to do so; (D) neither such Rights nor such rights or subscription agreement will include any provision that is unenforceable, that violates any applicable law or results in a default under or breach of any agreement or instrument binding upon the Company; (E) the terms of such Rights and such rights or subscription agreement and the issuance and sale of the Rights will comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company; and (F) such Rights or certificates representing such Rights will have been duly executed, countersigned, registered and delivered by the parties thereto (other than the Company) in accordance with the provisions of such rights or subscription agreement;

(xviii)      certificates representing shares of Company Stock will have been duly executed, countersigned, registered and delivered, or if uncertificated, valid book-entry notations will have been made in the share register of the Company, by the parties thereto (other than the Company) in each case in accordance with the provisions of the Certificate of Formation and Bylaws;

(xix)         there will be sufficient shares of Common Stock or Preferred Stock authorized under the Certificate of Formation and not otherwise issued or reserved for issuance;

(xx)          the purchase price for Company Stock payable to the Company or, if such shares are issuable on the conversion, exchange, redemption or exercise of another Security, the consideration payable to the Company for such conversion, exchange, redemption or exercise will not be less than the par value of such shares, or the lesser of such purchase price or such consideration, as the case may be, or the amount of such purchase price or such consideration, as the case may be, timely determined by the Board to constitute the stated capital applicable to such shares, in the case of shares of Preferred Stock; and

(xxi)         any Securities issuable upon conversion, exchange or exercise of any Securities being offered will have been duly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange or exercise.

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Based on the foregoing, and subject to the assumptions, qualifications, limitations and exceptions set forth herein, we are of the opinion that:

1.            With respect to any series of Debt Securities to be offered by the Company pursuant to the Registration Statement, when (a) the Board has taken all necessary corporate action to approve and establish the terms of such Debt Securities in accordance with the terms of the Indenture under which such Debt Securities will be issued, and such Debt Securities will not include any provision that is unenforceable, and to authorize and approve the issuance thereof; (b) the Indenture under which such Debt Securities will be issued will have become or will remain, as applicable, qualified under the Trust Indenture Act of 1939, as amended, and such qualification shall not have been terminated or rescinded; (c) the trustee will have been or will remain, as applicable, qualified to act as trustee under the Indenture under which such Debt Securities will be issued; (d) in the case of the senior Debt Securities, an indenture substantially in the form of the Senior Indenture under which such senior Debt Securities will be issued will have been duly authorized, executed and delivered by the Company and the trustee thereunder; (e) any supplemental indenture in respect of such Debt Securities has been duly authorized, executed and delivered by each party thereto; (f) certificates evidencing such Debt Securities complying with the terms of the Indenture under which such Debt Securities will be issued will have been duly authorized, executed, authenticated, issued and delivered in accordance with the provisions of such Indenture and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Debt Securities will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms.

2.            With respect to the Common Stock, when (a) the Board has taken all necessary corporate action to approve the issuance of the Common Stock, the terms of the offering and related matters; (b) there are a sufficient number of authorized but unissued shares of Common Stock; and (c) the Common Stock has been issued and delivered in accordance with the terms of the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Common Stock will be validly issued, fully paid and nonassessable.

3.            With respect to the Preferred Stock, when (a) the Board has taken all necessary corporate action to approve the issuance of the Preferred Stock, the terms of the offering and related matters, including the adoption of a certificate of designations relating to any Preferred Stock and the filing of the certificate of designations with the Secretary of State of the State of Texas; (b) there are a sufficient number of authorized but unissued shares of Preferred Stock; and (c) the Preferred Stock has been issued and delivered in accordance with the terms of the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Preferred Stock will be validly issued, fully paid and nonassessable.

4.            With respect to any Depositary Shares, when: (a) the related deposit agreement has been duly authorized and validly executed and delivered by the Company and by a depositary appointed by the Company (the “Depositary”) that meets the requirements for a depositary as described in the Registration Statement or the Prospectus Supplement for such offering and as provided in the applicable deposit agreement; (b) the Board has taken all necessary corporate action to approve the issuance of and establish the terms of the Depositary Shares and related shares of Preferred Stock, the terms of the offering thereof and related matters, including the adoption of resolutions relating to the preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends, qualifications, and terms and conditions of redemption of such related Preferred Stock (the “Related Preferred Stock Resolutions”); (c) the Related Preferred Stock Resolutions have been filed as part of a certificate of designations to the Company’s Certificate of Formation duly filed with the State of Texas and the related Deposit Agreement is governed by the law of the State of Texas; (d) the terms of the Depositary Shares and the related Preferred Stock and of the issuance and sale of each have been established so as to not violate any applicable law or the Company’s Certificate of Formation or Bylaws, or result in a default under or a breach of any agreement or instrument binding upon the Company and so as to comply with any requirements or restrictions imposed by any court, regulatory authority or other governmental body having jurisdiction over the Company; (e) the shares of the related Preferred Stock have been deposited with the Depositary; and (f) the depositary receipts representing the Depositary Shares have been duly executed, authenticated, countersigned, registered and issued, sold and delivered in the manner and for the consideration stated in the applicable deposit agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the depositary receipts evidencing the Depositary Shares will be validly issued and will entitle the holders thereof to the rights specified in the Deposit Agreement.

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5.            With respect to the Warrants, when (a) the Board has taken all necessary corporate action to approve the creation of and the issuance and terms of the Warrants, the terms of the offering thereof, and related matters; (b) a warrant agreement and any other agreements relating to the Warrants have been duly authorized and validly executed and delivered by the Company and the warrant agent appointed by the Company; and (c) the Warrants or certificates representing the Warrants have been duly executed and delivered in accordance with the applicable warrant agreement, any other agreements relating to the Warrants, and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Warrants will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms.

6.            With respect to the Purchase Contracts, when (a) the Board has taken all necessary corporate action to approve and establish the terms of the Purchase Contracts and to authorize and approve the issuance thereof, the terms of the offering thereof, and related matters; (b) a purchase agreement for the Purchase Contracts has been duly authorized and validly executed and delivered by the parties thereto; and (c) the Purchase Contracts have been duly executed and delivered in accordance with the purchase agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Purchase Contracts will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms.

7.            With respect to the Rights, when (a) the Board has taken all necessary corporate action to approve the creation of and the issuance and terms of the Rights, the terms of the offering thereof, and related matters; (b) a rights or subscription agreement and any other agreements relating to the Rights have been duly authorized and validly executed and delivered by the Company and the rights or subscription agent appointed by the Company; and (c) the Rights or certificates representing the Rights have been duly executed and delivered in accordance with the applicable rights or subscription agreement, any other agreements relating to the Rights, and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Rights will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms.

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8.             With respect to the Units, when (a) the Board has taken all necessary corporate action to approve and establish the terms of the Units and to authorize and approve the issuance thereof, the terms of the offering thereof, and related matters; (b) a unit agreement for the Units has been duly authorized and validly executed and delivered by the parties thereto; and (c) the Units have been duly executed and delivered in accordance with the unit agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration therefor provided for therein, then the Units will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms.

Our opinions in each of the paragraphs above are subject to applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfer or conveyance), reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally and to general principles of equity or public policy (regardless of whether enforcement is sought in a proceeding in equity or at law), including, without limitation, (a) the possible unavailability of specific performance, injunctive relief or any other equitable remedy, and (b) concepts of materiality, reasonableness, good faith and fair dealing, and we express no opinion herein with respect to provisions relating to severability or separability. The opinions expressed above are also subject to possible judicial action giving effect to governmental actions or foreign laws relating to or affecting creditors’ rights.

We express no opinions concerning (a) any provision that relates to severability or separability or purports to require that all amendments, supplements or waivers be in writing; or (b) the enforceability of indemnification provisions to the extent they purport to relate to liabilities resulting from or based upon negligence or any violation of federal or state securities or blue sky laws.

The foregoing opinions are limited in all respects to the laws of the State of Texas and the State of New York, and no opinion is expressed with respect to the laws of any other jurisdiction or any effect that such laws may have on the opinions expressed herein; provided, however, that the opinion in paragraph 1 above is limited to the laws of the State of New York that, in our professional judgment, are normally applicable to transactions of the type contemplated by the Indentures, and, with respect to the opinion in paragraph 1 above, we do not express any opinion herein concerning any other laws. This opinion is limited to the matters stated herein, and no opinion is implied or may be inferred beyond the matters expressly stated herein.

We express no opinion as to any matter other than as set forth in this letter, and no other opinion may be inferred or implied. Our opinion is given as of the date of this letter, and we undertake no, and disclaim any, obligation to advise you of any change in any matter set forth in this letter.

We hereby consent to the reference to our firm under the caption “Validity of the Securities” in the Prospectus and to the filing of this opinion as an exhibit to the Registration Statement. By giving such consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

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Very truly yours,

/s/ Norton Rose Fulbright US LLP

Norton Rose Fulbright US LLP