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): August 4, 2017

KLONDEX MINES LTD.
(Exact name of registrant as specified in its charter)

6110 Plumas Street, Suite A
Reno, Nevada 89519
(Address of Principal Executive Offices)

(775) 284-5757
(Registrant's telephone number, including area code)

N/A
(Former Name or Former Address, if Changed Since Last Report)

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 Instructions A.2 below):

[   ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

[   ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a -12)

[   ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d -2(b))

[   ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e -4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b -2 of this chapter).

Emerging growth company [X]

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. [   ]

Item 7.01 Regulation FD Disclosure.

On August 4, 2017, Klondex Mines Ltd. (the “Company”) filed a technical report concerning its Hollister mine titled “Technical Report and Pre-Feasibility Study for the Hollister Underground Mine” dated August 4, 2017, with an effective date of May 31, 2017 (the “Technical Report”) on SEDAR. On August 9, 2017, the Company filed an amended and restated version of the Technical Report (as amended and restated, the “Amended and Restated Technical Report”) on SEDAR. The Amended and Restated Technical Report is attached to this Current Report on Form 8-K as Exhibit 99.1. The format and content of the Amended and Restated Technical Report were prepared in accordance with Form 43-101F1 of National Instrument 43-101 – Standards of Disclosure for Mineral Projects of the Canadian Securities Administrators (“NI 43-101”).

In accordance with General Instruction B.2 of Form 8-K, the information set forth herein and in the Amended and Restated Technical Report attached hereto as Exhibit 99.1 shall not be deemed to be "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

As used in the Amended and Restated Technical Report, the terms “mineral reserve,” “proven mineral reserve” and “probable mineral reserve” are Canadian mining terms as defined in accordance with NI 43-101 and the Canadian Institute of Mining, Metallurgy and Petroleum (CIM)-CIM Definition Standards on Mineral Resources and Mineral Reserves, adopted by the CIM Council, as amended (“CIM Definition Standards”). These definitions differ from the definitions in the U.S. Securities and Exchange Commission's ("SEC") Industry Guide 7 (“SEC Industry Guide 7”) under the Exchange Act. The reserves identified in the Amended and Restated Technical Report have been estimated in accordance with both NI 43-101 and SEC Industry Guide 7.

The terms “mineral resource,” “measured mineral resource,” “indicated mineral resource” and “inferred mineral resource” are defined in, and required to be disclosed by NI 43-101; however, these terms are not defined terms under SEC Industry Guide 7 and are normally not permitted to be used in reports and registration statements filed with the SEC. Investors are cautioned not to assume that all or any part of a mineral deposit in these categories will ever be converted into reserves. “Inferred mineral resources” have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all, or any part, of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, except in rare cases. Investors are cautioned not to assume that all or any part of an inferred mineral resource exists or is economically or legally mineable.

Disclosure of “contained ounces” in a resource is permitted disclosure under Canadian regulations; however, the SEC normally only permits issuers to report in place tonnage and grade without reference to unit measures for mineralization that does not constitute “reserves” by SEC standards. Accordingly, information contained in the Amended and Restated Technical Report contain descriptions of the Company’s mineral deposits that may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder.

The term “mineralized material” as used in the Amended and Restated Technical Report, although permissible under SEC Industry Guide 7, does not indicate “reserves” by SEC Industry Guide 7 standards. Except as specified in the Amended and Restated Technical Report, the Company cannot be certain that any part of the mineralized material will ever be confirmed or converted into SEC Industry Guide 7 compliant “reserves”. Investors are cautioned not to assume that all or any part of the mineralized material will ever be confirmed or converted into reserves or that mineralized material can be economically or legally extracted.

Item 9.01 Financial Statements and Exhibits.

(d) List of Exhibits

SIGNATURE

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.

EXHIBIT INDEX