Exhibit 5.1

Andrews Kurth LLP 600 Travis, Suite 4200 Houston, Texas 77002 +1.713.220.4200 Phone +1.713.220.4285 Fax andrewskurth.com  

March 23, 2016

Basic Energy Services, Inc.
801 Cherry Street, Suite 2100
Fort Worth, Texas 76102

Ladies and Gentlemen:

We have acted as counsel to Basic Energy Services, Inc., a Delaware corporation (the “Company”), in connection with the preparation and filing of the Registration Statement on Form S-8 (the “Registration Statement”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to the issuance by the Company of up to an additional 1,000,000 shares (the “Shares”) of the Company’s common stock, par value $0.01 per share, under the Sixth Amended and Restated Basic Energy Services, Inc. 2003 Incentive Plan (the “Plan”). This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or any related prospectus, other than as expressly stated herein with respect to the issuance of Shares in accordance with the Plan.

As the basis for the opinions hereinafter expressed, we have examined: (i) originals or copies certified or otherwise identified to our satisfaction, of (a) the Registration Statement, (b) the Plan, (c) the Amended and Restated Certificate of Incorporation of the Company, as amended to date, (d) the Amended and Restated Bylaws of the Company, as amended to date, (e) certain resolutions of the Board of Directors of the Company certified to us to be true and correct by the Secretary of the Company, and (f) such other instruments and documents as we have deemed necessary or advisable for the purposes of this opinion, and (ii) such statutes, including the Delaware General Corporation Law (the “DGCL”), and regulations as we have deemed necessary or advisable for the purposes of this opinion. We have not independently verified any factual matter relating to this opinion.

In making our examination, we have assumed and have not verified (i) that all signatures on documents examined by us are genuine, (ii) the legal capacity of all natural persons, (iii) the authenticity of all documents submitted to us as originals and (iv) the conformity to the original documents of all documents submitted to us as certified, conformed or photostatic copies.

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Basic Energy Services, Inc.

March 23, 2016

Page 2

Based upon the foregoing, and subject to the limitations and assumptions set forth herein, and having due regard for such legal considerations as we deem relevant, we are of the opinion that:

1.Following the due authorization of a particular award by a duly constituted and acting committee of the Board of Directors of the Company, as provided in and in accordance with the Plan, the Shares issuable by the Company pursuant to such award will have been duly authorized.

2.Upon issuance and delivery of the Shares from time to time pursuant to the terms of the Plan and otherwise in accordance with the terms and conditions of the applicable award agreement, and upon receipt by the Company of lawful consideration therefor under the DGCL in accordance with the terms of the Plan, such Shares will be validly issued, fully paid and non-assessable.

We express no opinion other than as to the federal laws of the United States of America and the DGCL (including the statutory provisions, the applicable provisions of the Delaware Constitution and reported judicial decisions interpreting the foregoing). For purposes of this opinion, we assume that the Shares will be issued in compliance with all applicable state securities or blue sky laws.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement. In giving this consent, we do not thereby admit that we are included in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the SEC issued thereunder.

Our opinion is rendered as of the date hereof, and we assume no obligation to update or supplement our opinion to reflect any change of fact, circumstance or law after such time as the Registration Statement becomes effective.

Very truly yours,

/s/ Andrews Kurth LLP