State lemon law · checked October 23, 2026
Verified against the statute / official state publicationMont. Code §§61-4-501–61-4-533 (New Motor Vehicle Warranty Act)
| Presumption window | Montana's warranty period is the earlier of 2 years after delivery or 18,000 miles. |
|---|---|
| Same defect | 4+ repair attempts |
| Days out of service | 30+ business days — 30 or more BUSINESS days out of service. |
The presumption is the set of numbers that shifts the burden to the manufacturer. A claim can exist outside the presumption — it is a shortcut, not the whole road. Read why.
Deduction = miles driven before the vehicle's return ÷ 100,000 × purchase price.
Written notice to the manufacturer and a final opportunity to repair are required for the presumption to apply. Send it by certified mail.
Dispute route: A state-certified manufacturer's dispute procedure (§61-4-507) must be exhausted before the Act applies against that manufacturer.
Attorney's fees: Montana provides attorney's fees to a prevailing consumer.
The statute specifies no filing deadline; the Montana Dept. of Justice applies a filing period of 1 year after the earlier of 2 years after delivery or the first 18,000 miles.
| New vehicles | Covered |
|---|---|
| Leased vehicles | Covered |
| Used vehicles | Covered in defined situations — see notes |
| Motorcycles | Covered |
| RV / motor home | Covered — chassis / powertrain only |
Your repair-log tracker, the Montana notice letter, the buyback worksheet on Montana's formula, and your deadline calendar.
Checked October 23, 2026. Laws change; if your claim is close to a line, verify the current statute or ask a lawyer in Montana. This page is information, not legal advice.