Minors – Age of Majority – Montana
Minors and adults defined.
(1) Minors are:
(a) males under 18 years of age;
(b) females under 18 years of age.
(2) All other persons are adults.
Title 41, Chap. 1, Part 1, §41-1-101
Periods of minority — how calculated.
The periods specified in 41-1-101 must be calculated from the first minute of the day on which persons are born to the same minute of the corresponding day completing the period of minority.
Title 41, Chap. 1, Part 1, §41-1-102
A child conceived but not yet born is to be deemed an existing person, so far as may be necessary for its interests in the event of its subsequent birth.
Title 41, Chap. 1 Part 1, §41-1-103
Age of Majority
Occurs upon marriage (§40-6-234) or by judicial petition after reaching age 16 (§41-1-501)
Contracts may be disaffirmed within reasonable time after reaching 18, but necessities may not be disaffirmed (§41-1-301 et seq.)
Ability to Sue
Through general guardian or guardian ad litem (§41-1-202)
Consent to Medical Treatment
If emancipated; separated from parents and self-supporting; pregnant; has a communicable disease; or addicted to alcohol or drugs; has had a child or graduated from high school; needs emergency care (§41-1-402)