Post-Effective Amendment to Registration Statement (Form POS AM)

As filed with the Securities and Exchange Commission on March 4, 2026

No. 333-233875

No. 333-264138

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1 TO:

FORM S-3 REGISTRATION STATEMENT NO. 333-233875

FORM S-3 REGISTRATION STATEMENT NO. 333-264138

UNDER

THE SECURITIES ACT OF 1933

Nine Energy Service, Inc.

(Exact name of registrant as specified in its charter)

Delaware		80-0759121
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification Number)

2001 Kirby Drive, Suite 200

Houston, Texas 77019

(281) 730-5100

(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Theodore R. Moore

Executive Vice President, General Counsel and Secretary

2001 Kirby Drive, Suite 200

Houston, Texas 77019

(281) 730-5100

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Matthew R. Pacey, P.C.

Lanchi D. Huynh

Kirkland & Ellis LLP

609 Main Street, Suite 4700

Houston, Texas 77002

(713) 836-3600

Approximate date of commencement of proposed sale of the securities to the public: N/A. Removal from registration of securities that were not sold pursuant to these registration statements.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box: ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

	Large accelerated filer	☐	Accelerated filer	☐
	Non-accelerated filer	☒	Smaller reporting company	☒
			Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

DEREGISTRATION OF SECURITIES

These Post-Effective Amendments are being filed by Nine Energy Service, Inc. (the "Company") to deregister all securities remaining unsold under the following Registration Statements on Form S-3 (the "Registration Statements") filed by the Company with the Securities and Exchange Commission:

(1)

Registration Statement on Form S-3 (No. 333-233875), filed on September 20, 2019 and amended on November 8, 2019, registering an aggregate of 5,000,000 shares of common stock, par value $0.01 per share ("common stock"); and

(2)

Registration Statement on Form S-3 (No. 333-264138), filed on April 5, 2022, registering, among other things, 9,326,080 shares of common stock.

On February 1, 2026, the Company and certain of its subsidiaries filed voluntary petitions (the "Chapter 11 Cases") under chapter 11 of title 11 of the United States Code in the United States Bankruptcy Court for the Southern District of Texas to implement a prepackaged chapter 11 plan of reorganization. The Chapter 11 Cases are being jointly administered for administrative purposes only under the caption In re Nine Energy Service, Inc. et al.

As a result of the Chapter 11 Cases, the Company has terminated all offerings of securities pursuant to the Registration Statements. In accordance with an undertaking made by the Company in each of the Registration Statements to remove from registration, by means of a post-effective amendment, any of the securities that had been registered for issuance that remain unsold at the termination of such offering, the Company hereby removes from registration any and all securities registered but unsold under the Registration Statements, if any, as of the date hereof. The Registration Statements are hereby amended, as appropriate, to reflect the deregistration of such securities, and the Company hereby terminates the effectiveness of each of the Registration Statements.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused these Post-Effective Amendments to the Registration Statements on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in City of Houston, State of Texas, on March 4, 2026.

	NINE ENERGY SERVICE, INC.
	By:	/s/ Theodore R. Moore
	Name:	Theodore R. Moore
	Title:	Executive Vice President, General Counsel and Secretary

Note: No other person is required to sign these Post-Effective Amendments to the Registration Statements in reliance upon Rule 478 under the Securities Act of 1933, as amended.