UNITED STATES

SECURITIES
AND EXCHANGE COMMISSION

WASHINGTON,
D.C. 20549



FORM 10-K/A

Amendment No. 1



(Mark One)



|☒ | ANNUAL
    REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------
|  |                                                                                         

For the Fiscal Year Ended December 31,
2017

OR

|☐ | TRANSITION
    REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | --------------------------------------------------------------------------------------------



Commission File No. 0-30746



FRONTIER OILFIELD SERVICES INC.

(Exact name of registrant as specified in
its charter)



|Texas                                                          |  | 75-2592165                          
|-------------------------------------------------------------- |  | ------------------------------------
|(State or other jurisdiction of incorporation or organization) |  | (I.R.S. Employer Identification No.)
|                                                               |  |                                     
|220 Travis Street                                              |  |                                     
|Shreveport, Louisiana                                          |  | 71101                               
|(Address of Principal Executive Offices)                       |  | Zip Code                            



Registrant’s telephone number, including
Area Code: (972) 243-2610



Securities registered pursuant to Section
12(b) of the Act: None



Securities registered pursuant to Section
12(g) of the Act: Common Stock (Title of Each Class)



Indicate by check mark if the registrant is a well-known seasoned
issuer, as defined in Rule 405 of the Securities Act. ☐



Indicate by check mark if the registrant is not required to
file reports pursuant to Section 13 or Section 15(d) of the Act. ☐



Indicate by check mark whether the registrant (1) has filed
all reports to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such
shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for
the past 90 days. ☒  Yes  ☐  No



Indicate by check mark whether the registrant has submitted
electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted pursuant
to Rule 405 of Regulation S-T (§232.405 of this Chapter) during the presiding 12 months (or for such shorter period that the
registrant was required to submit and post such files). ☐  Yes  ☒  No



Indicate by check mark if disclosure of delinquent filers pursuant
to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge,
in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. ☒



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,” “non-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  ☒ | 
|(Do not check if a 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 13(a) of the Exchange Act. ☐



Indicate by check mark whether the registrant is a shell company
(as defined in Rule 12b-2 of the Act): ☐  Yes  ☒  No



On December 31, 2017, the aggregate market
value of voting and non-voting common equity held by non-affiliates of the registrant was approximately $2,423,054. The amount
was calculated by subtracting the total number of common shares held by officers, directors, and stockholders owning in excess
of 5% of the registrant’s common stock from the total number of shares and multiplying the remainder by the average of the
bid and asked price for the registrant’s common stock on December 29, 2017 as reported on the Over-The-Counter Pink Sheet
Market. As of March 28, 2018, the Company had 13,868,788 issued and outstanding shares of common stock.



Documents Incorporated by Reference: None
















EXPLANATORY NOTE

This Amendment No. 1 amends
the Annual Report on Form 10-K for the fiscal year ended December 31, 2017, which was filed with the Securities and Exchange
Commission on March 30, 2018, and is being filed solely to correct an administrative error in the content of Report of
Independent Registered Public Accounting Firm.

Other than as discussed above,
this Form 10-K/A does not update or amend any other information or any exhibits as originally filed on the Form 10-K and does not
otherwise reflect events occurring after the original filing date of the Form 10-K. Accordingly, this Form 10-K/A should be read
in conjunction with the Form 10-K and with other filings made by the issuing entity with the Securities and Exchange Commission
subsequent to the filing of the Form 10-K.











REPORT
OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM





To
the Board of Directors and Stockholders of Frontier Oilfield Services, Inc.



Opinion
on the Financial Statements



We
have audited the accompanying consolidated balance sheets of Frontier Oilfield Services, Inc. and its subsidiaries (the “Company”)
as of December 31, 2017 and 2016, and the related consolidated statements of operations, stockholders’ deficit and cash
flows for the years then ended, and the related notes (collectively referred to as the “consolidated financial statements”).
In our opinion, the consolidated financial statements present fairly, in all material respects, the consolidated financial position
of the Company as of December 31, 2017 and 2016, and the results of its consolidated operations and its cash flows for the years
then ended, in conformity with accounting principles generally accepted in the United States of America.



Explanatory
Paragraph – Going Concern



The
accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern.
As discussed in Note 2 to the consolidated financial statements, the Company has suffered recurring losses from operations since
inception and has a working capital deficiency both of which raise substantial doubt about its ability to continue as a going
concern. Management’s plans in regard to these matters are also described in Note 2. The consolidated financial statements
do not include any adjustments that might result from the outcome of this uncertainty.



Basis
for Opinion



These
consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an
opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered
with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with
respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities
and Exchange Commission and the PCAOB.



We
conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits
to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether
due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over
financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting
but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting.
Accordingly, we express no such opinion.





Our
audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether
due to error or fraud, and performing procedures that respond to those risks. Such procedures include examining, on a test basis,
evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the
accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the
consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.







/s/
Turner, Stone & Company, L.L.P.



Dallas,
Texas

March
29, 2018



We
have served as the Company’s auditor since 2006.











SIGNATURES



In accordance with Section 13 or 15(d) of
the Exchange Act, the registrant has caused this report to be signed on its behalf by the undersigned, thereunto duly authorized,
on the April 9, 2018.



|FRONTIER OILFIELD SERVICES, INC. |                                      
|-------------------------------- | -------------------------------------
|                                 |                                      
|Signature:                       | /s/ Don Lawhorne                     
|                                 | Don Lawhorne, Chief Executive Officer



In accordance with the Exchange Act, this
report has been signed by the following persons on behalf of the registrant and in the capacities indicated, on the April 9,
2018.



|Signatures               |  | Capacity                           | 
|------------------------ |  | ---------------------------------- | 
|                         |  |                                    | 
|/s/ Don Lawhorne         |  | Director, Chief Executive Officer  | 
|                         |  |                                    | 
|/s/ Bernard R. O’Donnell |  | Director, Executive Vice President | 
|                         |  |                                    | 
|/s/ John L. Stimpson     |  | Director                           | 





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