Exhibit 5.1

March 1, 2024

Group 1 Automotive, Inc.

800 Gessner, Suite 500

Houston, Texas 77024

Re: Registration Statement on Form S-3 (the “Registration Statement”)

Ladies and Gentlemen:

We have acted as counsel for Group 1 Automotive, Inc., a Delaware corporation (the “Company”) and Group 1 Realty, Inc., a Delaware corporation and a subsidiary of the Company (“Group 1 Realty”), with respect to certain legal matters in connection with the preparation and filing of a registration statement on Form S-3 (the “Registration Statement”) by the Company 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 (A) debt securities, which may be either senior or subordinated, in one or more series, consisting of notes, debentures or other evidences of indebtedness (the “Debt Securities”), which may be guaranteed by certain of the Company’s subsidiaries, including Group 1 Realty, Inc. (the “Subsidiary Guarantors”), (B) shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”), (C) shares of the Company’s preferred stock, in one or more series as determined by the board of directors (the “Board”) of the Company, (the “Preferred Stock”), (D) warrants to purchase Debt Securities, Common Stock or Preferred Stock (the “Warrants”), (E) rights to purchase Debt Securities, Common Stock, Preferred Stock or other securities (the “Rights”), (F) depositary shares evidenced by depositary receipts (the “Depositary Shares”) and (G) units consisting of one or more Debt Securities, shares of Common Stock or Preferred Stock, Warrants or any combination of such securities (the “Units” and, collectively with the Debt Securities, the Common Stock, the Preferred Stock, the Warrants, the Rights and the Depositary Shares, the “Securities”). 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 (each a “Prospectus Supplement”) to the Prospectus contained in the Registration Statement.

We have examined originals or copies, certified or otherwise identified to our satisfaction, of (i) the Third Amended and Restated Certificate of Incorporation and the Fourth Amended and Restated Bylaws of the Company, (ii) the Registration Statement, (iii) the form of Senior Indenture (the “Senior Indenture”), (iv) the form of Subordinated Indenture (the “Subordinated Indenture” and, together with the Senior Indenture, the “Indentures”), (v) the records of corporate proceedings that have occurred prior to the date hereof with respect to the Registration Statement, (vi) the bylaws and certificate of incorporation of Group 1 Realty and (vii) such other certificates, statutes and other instruments and documents as we considered appropriate for purposes of the opinions hereafter expressed. In addition, we reviewed such questions of law as we considered appropriate.

As to any facts material to the opinions contained herein, we have made no independent investigations of such facts and have relied, to the extent that we deem such reliance proper, upon certificates of public officials and officers or other representatives of the Company.

In connection with rendering the opinions set forth below, 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, (iii) all documents submitted to us as originals are authentic and all documents submitted to us as copies conform to the originals of those documents, (iv) the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective, (v) one or more Prospectus Supplements will have been prepared and filed with the Securities and Exchange Commission describing the Securities offered thereby and will comply with all applicable laws, (vi) all Securities will be issued and sold in compliance with applicable federal and state securities laws and in the manner specified in the Registration Statement and the applicable Prospectus

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Supplement, (vii) the Indentures relating to the Debt Securities, a warrant agreement (“Warrant Agreement”) relating to the Warrants, and a rights agreement relating to the Rights (“Rights Agreement”) will each be duly authorized, executed and delivered by the parties thereto, (viii) the form and terms of any Securities, the issuance, sale and delivery thereof by the Company and the Subsidiary Guarantors, as applicable, and the incurrence and performance of their obligations thereunder or in respect thereof in accordance with the terms thereof, will be in full compliance with, and will not violate, the formation documents and agreements of the Company and the Subsidiary Guarantors, as applicable, or any applicable law, rule, regulation, order, judgment, decree, award or agreement binding upon any of them, or to which the issuance, sale and delivery of such Securities, or the incurrence and performance of such obligations, may be subject, or violate any applicable public policy, or be subject to any defense in law or equity; (ix) each person signing the documents we examined has the legal capacity and authority to do so, (x) at the time of any offering or sale of any shares of Common Stock or Preferred Stock, that the Company shall have such number of shares of Common Stock or Preferred Stock, as set forth in such offering or sale, authorized or created and available for issuance, (xi) a definitive purchase, underwriting or similar agreement with respect to any Securities offered will have been duly authorized and validly executed and delivered by the Company and the other parties thereto and (xii) any Securities issuable upon conversion, exchange or exercise of any Debt Securities, Preferred Stock or Depositary Shares being offered will have been duly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange or exercise.

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 the Debt Securities, when (a) the applicable Indenture relating either to senior Debt Securities or subordinated Debt Securities and, if applicable, a related guarantee (the “Guarantee”) has been duly qualified under the Trust Indenture Act of 1939, as amended, (b) the Board (or a committee thereof) and the Subsidiary Guarantor have taken all necessary corporate action to approve the issuance and terms of any such Debt Securities and, if applicable, the related Guarantees, (c) the terms of such Debt Securities and, if applicable, the related Guarantees and of their issuance and sale have been duly established in conformity with the applicable Indenture so as not to violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company or the Subsidiary Guarantor and so as to comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company or the Subsidiary Guarantor, (d) any shares of Common Stock issuable upon the conversion of such Debt Securities, if applicable, have been duly and validly authorized for issuance and (e) such Debt Securities (which may include the related Guarantees) have been duly executed and authenticated in accordance with the applicable Indenture and issued and sold as contemplated in the Registration Statement and upon payment of the consideration for such Debt Securities as provided for in the applicable definitive purchase, underwriting or similar agreement, such Debt Securities and, if applicable, the related Guarantees will be legally issued and will constitute valid and legally binding obligations of the Company and the Subsidiary Guarantor, respectively, enforceable against the Company and the Subsidiary Guarantor in accordance with their terms, except as such enforcement is subject to any applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law);

2. With respect to shares of the Common Stock offered by the Company, when both (a) the Board has taken all necessary corporate action to approve the issuance and terms of the offering thereof and related matters and (b) certificates representing the shares of Common Stock have been duly executed, countersigned, registered and delivered (or non-certificated shares of Common Stock have been properly issued) either (i) in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board, then upon payment of the consideration therefor (not less than the par value of the Common Stock) provided for therein or (ii) upon conversion, exchange or exercise of any other Security in accordance with the terms of such Security or the instrument governing such Security providing for the conversion, exchange or exercise as approved by the Board, for the consideration approved by the Board (not less than the par value of the Common Stock), such shares of Common Stock will be legally issued, fully paid and non-assessable;

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3. With respect to shares of any series of Preferred Stock, when (a) the Board has taken all necessary corporate action to approve the issuance and terms of the shares of the series, the terms of the offering thereof and related matters, including the adoption of a resolution establishing and designating the series and fixing and determining the preferences, limitations and relative rights thereof and the filing of a statement with respect to the series with the Secretary of State of the State of Delaware (the “Certificate of Designation”) and (b) certificates representing the shares of the series of Preferred Stock have been duly executed, countersigned, registered and delivered (or non-certificated shares of Preferred Stock have been properly issued) either (i) in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board, then upon payment of the consideration therefor (not less than the par value of the Preferred Stock) provided for therein or (ii) upon conversion, exchange or exercise of any other Security in accordance with the terms of the Security or the instrument governing the Security providing for the conversion, exchange or exercise as approved by the Board, for the consideration approved by the Board (not less than the par value of the Preferred Stock), the shares of the series of Preferred Stock will be legally issued, fully paid and non-assessable;

4. With respect to the Warrants when (a) the Board has taken all necessary corporate action to approve the issuance and terms of the Warrants, the terms of the offering thereof and related matters, (b) the terms of any Warrants and of their issuance and sale have been duly established in conformity with the applicable Warrant Agreement so as not to violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company and (c) the Warrants have been duly executed and authenticated in accordance with the applicable Warrant Agreement and issued and sold as contemplated in the Registration Statement, the Warrants will constitute valid and legally binding obligations of the Company, subject to bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law);

5. With respect to the Rights, when (a) the Board has taken all necessary corporate action to approve the issuance and the terms of the Rights, the terms of the offering thereof and related matters, (b) the terms of any Rights and of their issuance and sale have been duly established in conformity with the applicable Rights Agreement so as not to violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company and (c) the Rights have been duly executed and authenticated in accordance with the applicable Rights Agreement and issued and sold as contemplated in the Registration Statement, the Rights will constitute valid and legally binding obligations of the Company, subject to bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law); and

6. With respect to the Depository Shares, when (a) the Company has taken all necessary corporate action to approve the issuance and terms of the Depositary Shares, the terms of the offering thereof and related matters, including the adoption of a Certificate of Designation relating to the Preferred Stock underlying the Depositary Shares and the filing of the Certificate of Designation with the Secretary of State of the State of Delaware, (b) the depositary agreement or agreements relating to the Depositary Shares and the related depositary receipts have been duly authorized and validly executed

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and delivered by the Company and the depositary appointed by the Company, (c) the shares of Preferred Stock underlying the Depositary Shares have been deposited with the depositary under the applicable depositary agreement and (d) the depositary receipts representing the Depositary Shares have been duly executed, countersigned, registered and delivered in accordance with the appropriate depositary agreement approved by the Company, either (i) upon payment of the consideration thereof or provided for in the applicable definitive purchase, underwriting or similar agreement or (ii) upon conversion, exchange or exercise of any other security in accordance with the terms of the Security or the instrument governing the Security providing for the conversion, exchange or exercise as approved by the Board, for the consideration as approved by the Board, the Depositary Shares will be legally issued.

We express no opinions concerning (a) the validity or enforceability of any provisions contained in the Indentures that purport to waive or not give effect to rights to notices, defenses, subrogation or other rights or benefits that cannot be effectively waived under applicable law, (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 or (c) the validity or enforceability of provisions that limit the obligations of a Subsidiary Guarantor based on the potential unenforceability, invalidity or voidability of a Guarantee under any applicable law, including, without limitation, any state or federal fraudulent transfer or fraudulent conveyance laws.

The foregoing opinions are limited to the laws of the States of New York and the Delaware General Corporation Law (including the applicable provisions of the Delaware Constitution and the reported judicial decisions interpreting these laws) and the federal laws of the United States of America.

We express no opinion as to the effect of the laws of any other jurisdiction, domestic or foreign, or to any matter other than as expressly set forth above, and no opinion on any other matter may be inferred or implied herefrom. The opinions expressed herein are given as of the date hereof, and we undertake no, and hereby disclaim any, obligation to advise you of any change in any matter set forth herein.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name in the Prospectus forming a part of the Registration Statement under the caption “Legal Matters.” In giving this consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act.

Very truly yours

/s/ Vinson & Elkins L.L.P.

Vinson & Elkins L.L.P.

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