Cover |
12 Months Ended |
|---|---|
|
Dec. 31, 2025
shares
| |
| Document Information [Line Items] | |
| Entity Registrant Name | NORTHERN DYNASTY MINERALS LTD |
| Entity Central Index Key | 0001164771 |
| Amendment Flag | true |
| Document Fiscal Period Focus | FY |
| Document Type | 40-F/A |
| Document Registration Statement | false |
| Document Annual Report | true |
| Document Period End Date | Dec. 31, 2025 |
| Current Fiscal Year End Date | --12-31 |
| Document Fiscal Year Focus | 2025 |
| Entity File Number | 001-32210 |
| Entity Incorporation, State or Country Code | Z4 |
| Entity Address, Address Line One | 14th Floor |
| Entity Address, Address Line Two | 1040 West Georgia Street |
| Entity Address, City or Town | Vancouver |
| Entity Address, State or Province | BC |
| Entity Address, Postal Zip Code | V6E 4H1 |
| City Area Code | 604 |
| Local Phone Number | 684-6365 |
| Title of 12(b) Security | Common Shares, no par value |
| Trading Symbol | NAK |
| Security Exchange Name | NYSE |
| Annual Information Form | true |
| Audited Annual Financial Statements | true |
| Entity Common Stock, Shares Outstanding | 558,461,162 |
| Entity Current Reporting Status | Yes |
| Entity Interactive Data Current | Yes |
| Entity Emerging Growth Company | false |
| ICFR Auditor Attestation Flag | true |
| Document Financial Statement Error Correction [Flag] | false |
| Amendment Description | Northern Dynasty Minerals Ltd (the “Company”) is filing this Amendment No. 1 (the “Amendment No. 1”) to its original Annual Report on Form 40-F for the year ended December 31, 2025 (the “Original 2025 Annual Report”) filed with the Securities and Exchange Commission (the “SEC”) on March 31, 2026, in order to provide (i) an updated consent of Deloitte LLP to include reference to the registration statement on Form F-10 (File No. 333-288224), as amended, which reference was inadvertently omitted in the consent of Deloitte LLP filed with the Original 2025 Annual Report, (ii) updated certifications of the Company’s Chief Executive Officer (“CEO”) and Chief Financial Officer (“CFO”) pursuant to Rule 13a-14(a) of the Exchange Act, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, and (iii) the Policy for the Recovery of Erroneously Awarded Incentive-Based Compensation (the “Compensation Clawback Policy”). The updated consent of Deloitte LLP is filed as Exhibit 99.8 to this Amendment No. 1. The updated CEO and CFO certifications are filed as Exhibits 99.4 and 99.5 to this Amendment No. 1. The Compensation Clawback Policy is filed as Exhibit 97.1 to this Amendment No. 1. This Amendment No. 1 consists of a cover page, this explanatory note, the signature page, the exhibit index, the updated consent of Deloitte LLP filed as Exhibit 99.8, the updated CEO and CFO certifications filed as Exhibits 99.4 and 99.5, and the Compensation Clawback Policy as Exhibit 97.1. Other than expressly set forth herein, this Amendment No. 1 does not, and does not purport to, amend or restate any other information contained in the Original 2025 Annual Report nor does this Amendment No. 1 reflect any events that have occurred after the Original 2025 Annual Report was filed. |
| Business Contact [Member] | |
| Document Information [Line Items] | |
| Entity Address, Address Line One | Suite 400 |
| Entity Address, Address Line Two | 2711 Centerville Road |
| Entity Address, City or Town | Wilmington |
| Entity Address, State or Province | DE |
| Entity Address, Postal Zip Code | 19808 |
| City Area Code | 800 |
| Local Phone Number | 927-9800 |
| Contact Personnel Name | Corporation Service Company |