Bentonite Production Tax


All bentonite producers must file a Bentonite Production Tax return every six months.

Tax Rates

We calculate the bentonite production tax rates every year using the formula found in 15-39-101, MCA.

Montana taxes bentonite per ton before crushing and drying.

Wet Tons Per YearTax Per Ton
First 20,000$0.00
20,001—100,000$1.96
100,001—250,000$1.88
250,001—500,000$1.76
500,001—1,000,000$1.57
Over 1,000,000$1.26

Reporting, Paying, and Due Dates

Bentonite Production Tax returns are due twice each year:

Period EndingDue Date
June 30August 14
December 31February 14

You may:

Related Laws

15-39-101, MCA