Montana campaign-finance filing deadlines
Official 2026 report due dates for Montana state candidates file with Montana Commissioner of Political Practices (COPP).
9 report deadlines for the 2026 cycle.
These are the campaign-finance report due dates a Montana state candidate files with Montana Commissioner of Political Practices (COPP) for the 2026 election cycle, stored verbatim from the official schedule. The 2026 primary is Jun 2, 2026.
| Due | Type | Report | Covers |
|---|---|---|---|
| Jan 5, 2026 | Annual/Year-end | MT 2025 Year-End Report Year-end C-5 covering October 1 – December 31, 2025. |
Oct 1, 2025 – Dec 31, 2025 |
| Mar 20, 2026 | Pre-election | MT Pre-Primary Report 1 C-5 covering January 1 – March 15, 2026. |
Jan 1, 2026 – Mar 15, 2026 |
| Apr 20, 2026 | Pre-election | MT Pre-Primary Report 2 C-5 covering March 16 – April 15, 2026. |
Mar 16, 2026 – Apr 15, 2026 |
| May 20, 2026 | Pre-election | MT Pre-Primary Report 3 Last C-5 before the June 2 primary; covers April 16 – May 14, 2026. |
Apr 16, 2026 – May 14, 2026 |
| Jun 20, 2026 | Post-election | MT Post-Primary Report C-5 covering May 15 – June 15, 2026 (June 20 is a Saturday — file early). |
May 15, 2026 – Jun 15, 2026 |
| Aug 20, 2026 | Periodic | MT Summer Report C-5 covering June 16 – August 15, 2026 (no July report by statute). |
Jun 16, 2026 – Aug 15, 2026 |
| Sep 20, 2026 | Pre-election | MT Pre-General Report 1 C-5 covering August 16 – September 15, 2026 (September 20 is a Sunday — file early). |
Aug 16, 2026 – Sep 15, 2026 |
| Oct 20, 2026 | Pre-election | MT Pre-General Report 2 Last C-5 before the November 3 general; covers September 16 – October 14, 2026. |
Sep 16, 2026 – Oct 14, 2026 |
| Nov 20, 2026 | Post-election | MT Post-General Report Final scheduled C-5; covers October 15 – November 15, 2026. |
Oct 15, 2026 – Nov 15, 2026 |
Shaded rows are deadlines that have already passed.
Good to know
Montana requires a Form C-5 for every reporting period (even a $0 report). Two published due dates fall on a weekend — June 20 (Saturday) and September 20 (Sunday); the campaign-finance statute has no next-business-day extension, so treat the published date as the hard deadline and file on or before the preceding Friday. Event-driven C-7/C-7E 48-hour reports apply for a single contribution or expenditure over $790 (statewide) / $450 (other) in the windows before each election.
Electbase compiles these dates from official state sources as a workflow aid. It is not legal advice. Confirm every deadline with your filing authority before you rely on it.
Last updated July 13, 2026