Cannabis in Montana is legal for both medical and adult use.

Montana legalized cannabis for medical use in 2004 through  voter initiative I 148. The state similarly authorized cannabis for adult use in the 2020 election through voter Initiative 190 which went into effect January 1, 2021.

Administrative rules related to Montana’s adult use Cannabis framework  can be found in Title 42, Chapter 39 of the Administrative Rules of Montana

Within Montana’s adult use framework adults 21+ may possess, purchase, obtain, use or transport up to 1 ounce of usable marijuana, except that not more than 8 grams may be in a concentrated form and not more than 800 milligrams of THC may be in edible marijuana products meant to be eaten or swallowed in solid form.

Adults may cultivate up to two mature marijuana plants and two seedlings for private use in a private residence, subject to certain restrictions.Within Montana’s medical framework, patients may possess up to 1ounce but may purchase a maximum of 5 ounces of usable marijuana a month and no more than 1 ounce of usable marijuana a day.

Medical cardholders may cultivate up to four mature plants and four seedlings for private use in a private residence.