Prospectus Supplement No. 10 Filed Pursuant to Rule 424(b)(3)

(to Prospectus dated June 3, 2020)

Registration Statement No. 333-237748

PROSPECTUS SUPPLEMENT NO. 10

Atlas Technical Consultants, Inc.

27,780,345 Shares of Class A Common Stock

This prospectus supplement No. 10 (this “Prospectus Supplement”) updates, amends and supplements the prospectus dated June 3, 2020, as supplemented (the “Prospectus”), which forms a part of our registration statement on Form S-1, File No. 333-237748 (the “Registration Statement”) relating to the resale by the selling security holders named in this prospectus or their permitted transferees of up to 27,780,345 shares of our Class A common stock, 3,805,977 of which represent shares of Class A common stock held by certain selling security holders named in this prospectus and 23,974,368 of which represent shares of Class A common stock that may be issued from time to time, pursuant to the amended and restated limited liability company agreement of Atlas TC Holdings LLC, a subsidiary of the Company (“Holdings”), dated February 14, 2020 (the “LLC Agreement”), to certain members of Holdings, that own units in Holdings (“Holdings Units”), upon exchange of such members’ Holdings Units, together with an equal number of shares of our Class B common stock, par value $0.0001 per share (“Class B common stock”), which were issued to AS&M Holdings LP, a Delaware limited partnership (formerly known as “Atlas Technical Consultants Holdings LP,” referred to herein as “AS&M Holdings”), in connection with, and as part of the consideration for, our business combination (the “Business Combination”) with Atlas Intermediate Holdings LLC, a Delaware limited liability company (“Atlas Intermediate”), which we consummated on February 14, 2020.

The selling security holders may offer, sell or distribute shares of Class A common stock publicly or through private transactions at prevailing market prices or at negotiated prices. We will not receive any of the proceeds from the sale of shares of Class A common stock owned by the selling security holders. We will bear all costs, expenses and fees in connection with the registration of these shares of Class A common stock, including with regard to compliance with state securities or “blue sky” laws. The selling security holders will bear all commissions and discounts, if any, attributable to their sale of shares of Class A common stock.

This Prospectus was previously updated in order to reflect the distribution and transfer (the “Distribution”) of 2,537,382 Holdings Units that were already included in the Registration Statement, together with an equal number of shares of Class B common stock, from AS&M Holdings to certain of its limited partners (the “Transferees”). This Prospectus Supplement is being filed to, among other things, update the selling security holders table included in the Prospectus in order to reflect (i) the distribution and transfer (the “BCP Distribution”) of 17,636,001 Holdings Units that were already included in the Registration Statement, together with an equal number of shares of Class B common stock, from AS&M Holdings to certain of its limited partners (the “BCP Transferees”) and (ii) immediately following the BCP Distribution, the transfer (the “AS&M Distribution,” and together with the BCP Distribution, the “AS&M Transfers”) of 2,940,857 Holdings Units that were already included in the Registration Statement, together with an equal number of shares of Class B common stock, from AS&M Management LLC, a Delaware limited liability company (formerly known as “Atlas Technical Consultants Management LLC,” referred to herein as “AS&M Management”) to certain of its members (the “Subsequent Transferees”). Certain of the BCP Transferees and Subsequent Transferees have elected to be included in the updated selling security holders table included in the Prospectus, and certain of the BCP Transferees and Subsequent Transferees may elect to be included in the selling security holders table in future supplements to the Prospectus. The Holdings Units and Class B common stock subject to the AS&M Transfers were already included in the Registration Statement. This Prospectus Supplement does not include any new or additional shares that were not already reflected in the Prospectus.

The attached information updates, amends and supplements certain information contained in the Prospectus. To the extent information in this Prospectus Supplement differs from, updates or conflicts with information contained in the Prospectus, the information in this Prospectus Supplement is the more current information. This Prospectus Supplement is not complete without, and should not be delivered or utilized, except in conjunction with the Prospectus, including any supplements and amendments thereto. You should read this Prospectus Supplement in conjunction with the Prospectus, including any supplements and amendments thereto.

Our Class A common stock is traded on The NASDAQ Stock Market (“NASDAQ”) under the symbol “ATCX”. On February 12, 2021, the last reported sale price of our Class A common stock was $8.85 per share. As of February 12, 2021, we had 15,003,962 shares of Class A common stock issued and outstanding and 20,276,450 shares of Class B common stock issued and outstanding.

Investing in our securities involves risks. See “Risk Factors” beginning on page 5 of the Prospectus.

We are an “emerging growth company” as defined in Section 2(a) of the Securities Act of 1933, as amended (the “Securities Act”), and are subject to reduced public company reporting requirements. See “Risk Factors.”

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is February 16, 2021.

Selling Security Holders

The selling security holders may offer and sell, from time to time, up to 27,780,345 shares of Class A common stock, which includes 3,805,977 shares of Class A common stock held by certain selling security holders named in this prospectus and 23,974,368 shares of Class A common stock that may be issued from time to time to certain members of Atlas Holdings, that own units in Holdings Units, upon exchange of such members’ Holdings Units, together with an equal number of shares of our Class B common stock. The term “selling security holders” includes the stockholders listed in the table below and their permitted transferees.

The following table has been updated to reflect the AS&M Transfers as discussed above and provides, as of February 16, 2021, information regarding the beneficial ownership of the Class A common stock held by each of the selling security holders, the number of shares of Class A common stock that may be sold by each selling security holder under this prospectus and that each selling security holder will beneficially own after this offering.

Because each selling security holder may dispose of all, none or some portion of their securities, no estimate can be given as to the number of securities that will be beneficially owned by a selling security holder upon termination of this offering. For purposes of the table below, however, we have assumed that after termination of this offering none of the securities covered by this prospectus will be beneficially owned by the selling security holders and further assumed that the selling security holders will not acquire beneficial ownership of any additional securities during the offering. In addition, the selling security holders may have sold, transferred or otherwise disposed of, or may sell, transfer or otherwise dispose of, at any time and from time to time, our securities in transactions exempt from the registration requirements of the Securities Act after the date on which the information in the table is presented.

We may amend or supplement this prospectus from time to time in the future to update or change this selling security holders list and the securities that may be resold.

Beneficial ownership is determined in accordance with the rules of the SEC and includes voting or investment power with respect to shares of Class A common stock and the right to acquire such voting or investment power within 60 days through the exercise of any option, warrant or other right. Unless otherwise indicated below, to our knowledge, all persons named in the table have sole voting and investment power with respect to the shares of Class A common stock beneficially owned by them. Except as described in the footnotes to the following table and under “Certain Relationships and Related Party Transactions” below, none of the persons named in the table has held any position or office or had any other material relationship with us or our affiliates during the three years prior to the date of this prospectus. The inclusion of shares of Class A common stock in this table does not constitute an admission of beneficial ownership for the person named below.

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