MONTANA CODE ANNOTATED § 40-1-212
Effective period of license
A license to marry is effective upon issuance and expires after 180 days.
En. 48-307 by Sec. 7, Ch. 536, L. 1975; R.C.M. 1947, 48-307; amd. Sec. 1, Ch. 7, L. 1987.