Updated September 7, 2026. Quick answer: In Montana, you have the later of 12 months from informal probate or 3 years from the date of death to contest a will that has already been admitted to probate, running from whichever of those two events is later.
How long do you have to contest a will in Montana?
| Deadline to contest an admitted will | the later of 12 months from informal probate or 3 years from the date of death |
| What starts the clock | whichever of those two events is later |
| Dedicated will-contest statute? | Yes |
“No informal probate or appointment proceeding or formal testacy or appointment proceeding…may be commenced more than 3 years after the decedent’s death…A proceeding to contest an informally probated will and to secure appointment of the person with legal priority for appointment in the event the contest is successful may be commenced within the later of 12 months from the informal probate or 3 years from the decedent’s death.”
Source: Mont. Code Ann. § 72-3-122
What makes Montana different
Montana follows the standard Uniform Probate Code ‘later of’ formula, and expressly carves proceedings to construe an already-probated will or determine heirs out of the time bar entirely. The controlling authority is Mont. Code Ann. § 72-3-122, and the window runs from whichever of those two events is later.
What happens once this deadline passes?
Once the window above closes, Montana’s probate of the will generally becomes final and binding on everyone who had the chance to object, subject only to the tolling or discovery exceptions described above; a separate objection Montana allowed at the original probate hearing does not reopen or extend it.
Sources
| Statute / rule | Mont. Code Ann. § 72-3-122 |
| Montana courts (general reference) | Montana judicial branch |
| Confidence | High |
Every statute or rule quoted on this Montana page was read directly from the state’s own legislature/court/code site this session, or, where that site blocked automated access, from a reputable legal-citation mirror quoting the same official text with its official citation (disclosed below). General information, not legal advice; whether a specific contest is still timely can turn on facts (exactly when notice was given, how the will was probated, whether a disability applies) that only your own Montana probate court file can confirm.