Mont. Code Ann. § 7-4-4211

A person employed by a municipality may file with the appointing power a designation of a person who, notwithstanding any other provision of law, is entitled, on the death of the employee, to receive all warrants or paychecks that would have been payable to the decedent. The employee may change the designation from time to time. A designated person shall claim the warrants or paychecks from the city treasurer or town clerk, whichever is applicable, and on sufficient proof of identity, the city treasurer or town clerk shall reissue the warrant or paycheck in the name of the designated person and deliver the warrant or paycheck to the designated person.