EX-5.1

Exhibit 5.1

LOGO

767 Fifth Avenue

New York, NY 10153-0119

+1 212 310 8000 tel

+1 212 310 8007 fax

August 1, 2023

NCS Multistage Holdings, Inc.

19350 State Highway 249

Suite 600

Houston, TX 77070

Ladies and Gentlemen:

We have acted as counsel to NCS Multistage Holdings, Inc., a Delaware corporation (the “Company”), in connection with the preparation and filing with the Securities and Exchange Commission of the Company’s Registration Statement (the “Registration Statement”) on Form S-8 under the Securities Act of 1933, as amended (the “Securities Act”), relating to the registration of 75,000 additional shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”), pursuant to the Amended and Restated 2017 Equity Incentive Plan (the “Plan”).

In so acting, we have examined originals or copies (certified or otherwise identified to our satisfaction) of (i) the Second Amended and Restated Certificate of Incorporation of the Company; (ii) the Certificate of Amendment to the Second Amended and Restated Certificate of Incorporation of the Company, effective as of December 1, 2020; (iii) the Amended and Restated Bylaws of the Company; (iv) the Plan; (v) the Registration Statement; and (vi) such corporate records, agreements, documents and other instruments, and such certificates or comparable documents of public officials and of officers and representatives of the Company, and have made such inquiries of such officers and representatives, as we have deemed relevant and necessary as a basis for the opinion hereinafter set forth.

In such examination, we have assumed the genuineness of all signatures, the legal capacity of all natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as certified, conformed or photostatic copies, and the authenticity of the originals of such latter documents. As to all questions of fact material to this opinion that have not been independently established, we have relied upon certificates or comparable documents of officers and representatives of the Company.

Based on the foregoing, and subject to the qualifications stated herein, we are of the opinion that the 75,000 shares of Common Stock being registered for sale under the Plan pursuant to the Registration Statement have been duly authorized and, when issued and delivered in accordance with the terms of the Plan, will be validly issued, fully paid and non-assessable.

The opinion expressed herein is limited to the corporate laws of the State of Delaware, and we express no opinion as to the effect on matters covered by this letter of the laws of any other jurisdiction.