Mont. Code Ann. § 7-2-2741

7-2-2741 . Processing of claims against abandoned county. (1) All claims and demands against any abandoned and abolished county for salaries, services, wages, materials, and supplies; for all other current expenses; and for claims and demands accruing under contracts and for which said county was liable at the time it ceased to exist and which had not been approved and warrants issued therefor prior to the time it ceased to exist shall be presented to the board of county commissioners of the county designated in the petition for abandonment as the county to which its territory is attached and made a part. Except as provided in subsection (2), all such claims and demands shall be acted on by the board of such county, and warrants shall be issued in payment thereof in the same manner as though the same had been incurred by such county.

(2) All such warrants shall be drawn and issued against the proper funds of such abandoned and abolished county. No such claim or demand shall be approved or warrant issued in payment thereof if the amount of such claim or demand exceeds the unexpended balance of appropriation for such purpose contained in the budget of the abandoned and abolished county for the year in which the same was incurred.