Mont. Code Ann. § 7-4-2104
(1) At each general election, the member or members of the board of county commissioners to be elected must be selected from the residents and electors of the district or districts in which the vacancy occurs, but the election of the member or members of the board must be submitted to the entire electorate of the county unless otherwise provided for under:
History: En. 16-902.3 by Sec. 3, Ch. 298, L. 1974; R.C.M. 1947, 16-902.3; amd. Sec. 1, Ch. 224, L. 1987; amd. Sec. 1, Ch. 183, L. 2001; amd. Sec. 4, Ch. 291, L. 2009; amd. Sec. 5, Ch. 262, L. 2015.