MMG tax value is 3% of annual gross proceeds (15-23-801, MCA). Local mill levies apply to this value to determine the tax.
Determining Gross Proceeds
Gross proceeds are the payment or refined metal received by the mine from the metal trader, smelter, roaster, or refinery, multiplied by the quoted price minus allowed costs.
Mines producing less than 20,000 tons of ore in a year are exempt from property tax on half of the gross proceeds. (15-6-208, MCA)
Metal traders, smelters, roasters, and refineries specify the allowed costs in the contract. These costs may include:
- Basic treatment and refinery charges
- Quantity deductions
- Price deductions
- Penalty metal deductions
- Impurity deductions
- Moisture deductions
Reporting and Payment Options
File through our TransAction Portal (TAP).
County treasurers distribute the Metal Mines Gross Proceeds Tax to taxing jurisdictions based on their associated relative economic impact.
Hard-rock mining operations are subject to hard-rock mining impact property tax base sharing laws.