UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 6, 2016

PIONEER ENERGY SERVICES CORP.

(Exact name of registrant as specified in its charter)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

On December 6, 2016, Pioneer Energy Services Corp. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Goldman, Sachs & Co. as representative of the several underwriters listed on Schedule A thereto (collectively, the “Underwriters”). Pursuant to the Underwriting Agreement, the Company agreed to sell to the Underwriters an aggregate of 10,500,000 shares of common stock of the Company (the “Common Stock”) at a price to the Underwriters of $5.4481 and an initial price to the public of $5.75. The Company also granted the Underwriters a 30-day option to purchase up to an additional 1,575,000 shares of Common Stock on the same terms. The total proceeds (before estimated offering expenses) to the Company from the sale of the initial 10,500,000 shares of Common Stock are expected to be approximately $57,205,050.

The Underwriting Agreement contains customary representations, warranties and agreements of the parties, and customary conditions to closing, obligations of the parties and termination provisions. The Company has agreed to indemnify the Underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribute to payments the Underwriters may be required to make in respect of those liabilities.

The offering is expected to close on December 12, 2016, subject to customary closing conditions.

The Underwriters and their affiliates have provided in the past to the Company and its affiliates and may provide from time to time in the future certain commercial banking, financial advisory, investment banking and other services for the Company and such affiliates in the ordinary course of their business, for which they have received and may continue to receive customary fees and commissions. In addition, from time to time, the Underwriters and their affiliates may effect transactions for their own account or the account of customers, and hold on behalf of themselves or their customers, long or short positions in our debt or equity securities or loans, and may do so in the future.

The foregoing description of the Underwriting Agreement in this Current Report on Form 8-K is qualified in its entirety by reference to the complete text of the Underwriting Agreement, a copy of which is filed as Exhibit 1.1 hereto and incorporated into this Item 1.01 by reference.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

INDEX TO EXHIBITS