(1) Whenever a vacancy occurs in the house of representatives, the appointee shall serve until the end of the term to which the predecessor was elected. (2) Whenever a vacancy occurs in the senate, the appointee shall serve until a successor can be elected as provided in 5-2-406.
Term Of Appointee
Mont. Code Ann. § 5-2-405, under Vacancies.
Mont. Code Ann. § 5-2-405