Company: FORFF
Filing Date: 2025-11-04
Form Type: 6-K
Source: 0001666175-25-000051
Chunk: 0

Company: Fortis Inc.
Filing Date: 2025-11-04
Form: 6-K
Chunk 0
---
### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549
<div align='center'>FORM 6-K</div>

### REPORT OF FOREIGN PRIVATE ISSUER

#### PURSUANT TO RULE 13a-16 OR 15d-16

#### OF THE SECURITIES EXCHANGE ACT OF 1934

#### For the month of November, 2025
<div align='center'>Commission File Number: 001-37915</div>

#### Fortis Inc.

#### Fortis Place, Suite 1100

#### 5 Springdale Street

#### St. John's, Newfoundland and Labrador

#### Canada, A1E 0E4
<div align='center'>(Address of Principal Executive Office)</div>

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

### INCORPORATION BY REFERENCE
The registrant's unaudited condensed consolidated interim financial statements as at and for the nine months ended September 30, 2025, together with the notes thereto, furnished as Exhibit 99.2 to this report on Form 6-K, and the registrant's management discussion and analysis of financial condition and results of operations for the same period furnished as Exhibit 99.3 to this report on Form 6-K, are incorporated by reference into the following Registration Statements of the Registrant, as amended or supplemented: Form S-8 (File No. 333-226663), Form S-8 (File No. 333-236213), Form F-3 (File No. 333-279253), Form F-10 (File No. 333-283687), Form S-8 (File No. 333-264838), Form S-8 (File No. 333-276111) and Form S-8 (File No. 333-276112), and Form S-8 (File No. 333-281205).

<div align='center'>EXHIBITS</div>

| Exhibit 
 99.1    
 99.2    |     | Description                                                                                                                                                      
 Fortis Inc. Press Release datedNovember4, 2025                                                                                                                   
 Unaudited Condensed Consolidated Interim Financial Statements of Fortis Inc. as at and for theninemonths endedSeptember30, 2025, together with the