FTS Fortis Inc

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE

SECURITIES EXCHANGE ACT OF 1934

For the month of December, 2018

Commission File Number 001-37915

FORTIS INC.

(Translation of registrant’s name into English)

Fortis Place, Suite 1100

5 Springdale Street

St. John’s, Newfoundland and Labrador

Canada, A1E 0E4

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F o                         Form 40-F x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  o

INCORPORATION BY REFERENCE

The exhibits to this report on Form 6-K are hereby incorporated by reference into the registrant’s Registration Statement on Form F-10 (File No. 333-228593), as amended and supplemented, and are made part thereof and exhibits thereto from the date on which this report is furnished, to the extent not superseded by documents or reports subsequently filed or furnished.

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