UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q/A

(Amendment No. 1)

(Mark One)

For the quarterly period ended March 31, 2018

OR

For the transition period from                 to                

Commission File Number: 001-38484

Spirit of Texas Bancshares, Inc.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (936) 521-1836

Indicate by check mark whether the registrant (1) has filed all reports required 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 Web site, 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 preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ☒    No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, 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.

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 Exchange Act).    Yes  ☐    No  ☒

As of May 25, 2018, the registrant had 9,786,611 shares of common stock, no par value, outstanding.

EXPLANATORY NOTE

This Amendment No. 1 (this “Amendment”) to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018, which was originally filed on June 1, 2018 (the “Original Filing”) is being filed for the sole purpose of furnishing Exhibit 101 to the Form 10-Q in accordance with Rule 405 of Regulation S-T.  Exhibit 101 to this Amendment No. 1 provides the consolidated financial statements and related notes from the Form 10-Q formatted in XBRL (eXtensible Business Reporting Language). This Amendment is being filed within the time period provided by Rule 405(a)(2) of Regulation S-T.

No other changes have been made to the Original Form 10-Q except for the furnishing of the exhibits described above. This Amendment does not reflect subsequent events occurring after the date of the Original Form 10-Q or modify or update any disclosures set forth in the Original Form 10-Q.

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Item 6.        Exhibits

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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 thereunto duly authorized.

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