Value of a Mill

The procedure for calculating an allowable mill levy is outlined in 15-10-420, MCA. 

Procedure for calculating levy.

(1) (a) Subject to the provisions of this section, a governmental entity that is authorized to impose mills may impose a mill levy sufficient to generate the amount of property taxes actually assessed in the prior year plus one-half of the average rate of inflation for the prior 3 years. The maximum number of mills that a governmental entity may impose is established by calculating the number of mills required to generate the amount of property tax actually assessed in the governmental unit in the prior year based on the current year taxable value, less the current year's newly taxable value, plus one-half of the average rate of inflation for the prior 3 years. 

There are limits to how much a local government can levy. To exceed the maximum levy, they must place a vote on the ballot. Local governments cannot easily raise funds for the general fund. This is why they may ask library boards and directors to consider a voted levy per 22-1-304, MCA or 22-1-709, MCA for district libraries.