An extension to file is not an extension to pay tax.
Montana grants every individual taxpayer an automatic extension of up to six months to file, with no application required. The extension only moves the filing deadline - taxes, penalties, and interest are still computed from the original due date, so any balance due should be paid by the regular deadline to limit interest and avoid the late-payment penalty. The Department may grant additional time beyond six months for good cause.
| Item | Detail |
|---|---|
| Form required | None |
| Extension length | Up to 6 months following the date prescribed for filing; the Department may allow further time for good cause |
| Payment | Not extended - taxes, penalties, and interest continue to run from the original due date |
| Authority | Mont. Code Ann. §15-30-2604(3)(a) |