The following individuals who otherwise meet the requirements of this title are eligible to adopt a child: (1) a husband and wife jointly or either the husband or wife if the other spouse is a parent of the child; (2) an unmarried individual who is at least 18 years of age; or (3) a married individual at least 18 years of age who is legally separated from the other spouse or whose spouse has judicially been declared incompetent.
Who May Adopt
Mont. Code Ann. § 42-1-106, under Adoption Policy and Procedures.
Mont. Code Ann. § 42-1-106