Mont. Code Ann. § 1-5-629
Authority and venue for notarial acts
1-5-629 . Authority and venue for notarial acts. (1) A notary public may perform a notarial act within the jurisdiction authorized in the notary's commission from the secretary of state.
(2) The venue for a notarial act is the state and the county where the notarial officer is physically located at the time the notarial act is performed.