UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

(Amendment No. 1)

(Mark One)

For the fiscal year ended December 31, 2017

or

For the transition period from ___________ to ___________

Commission file number: 001-36822

InfraREIT, Inc.

(Exact name of Registrant as specified in its charter)

(214) 855-6700

(Registrant’s Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:

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

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ☒    No  ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ☐    No  ☒

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 if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of the 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 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 Act).    Yes  ☐    No  ☒

As of June 30, 2017, the last business day of the registrant’s most recently completed second fiscal quarter, the aggregate market value of Common Stock held by non-affiliates of the registrant was $638.8 million based on the last sales price on June 30, 2017 on the New York Stock Exchange of $19.15 for the registrant’s Common Stock.

As of February 23, 2018, 43,796,915 shares of common stock were issued and outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the proxy statement for the registrant’s 2018 Annual Meeting of Stockholders to be held May 16, 2018 are incorporated in Part III of this Annual Report on Form 10-K.

EXPLANATORY NOTE

InfraREIT, Inc. (the Company) is filing this Amendment No. 1 on Form 10-K/A (Amended Filing) to amend its Annual Report on Form 10-K for the year ended December 31, 2017 filed with the U.S. Securities and Exchange Commission (SEC) on March 5, 2018 (Original Filing). This Amended Filing is being filed solely to include the consolidated financial statements of Sharyland Utilities, L.P. (Sharyland), the Company’s sole tenant, in Item 15 of Part IV in accordance with Section 2340 of the SEC Financial Reporting Manual. Because the Company’s assets are leased to Sharyland under triple-net leases that transfer substantially all operating costs to Sharyland, financial information about Sharyland may be relevant to investors. Sharyland’s financial statements were provided to the Company by Sharyland, and the Company did not participate in their preparation or review.

Item 15 of Part IV is the only portion of the Original Filing being amended by this Amended Filing. Accordingly, except as described above and specifically noted in the exhibit list below, this Amended Filing does not otherwise update any exhibits as originally filed and does not, and does not purport to, update or restate the information in any other Item of the Original Filing or otherwise reflect events that occurred after the filing date of the Original Filing.

PART IV

(a) Documents filed as part of report on Form 10-K

1. Financial Statements

The financial statements were previously filed with the Original Filing.

2. Financial Statement Schedules

The financial statements were previously filed with the Original Filing.

3. Exhibits

1

2

3

4

5

6

SIGNATURES

Pursuant to the requirements of Section 13 and 15(d) 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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