Montana Title 15. Taxation § 15-65-115. Failure to pay or file--penalty and interest--review--interest

(3)(a) If a seller fails to file the report required by 15-65-112 or if the department determines that the report understates the amount of tax due, the department may determine the amount of the tax due and assess that amount against the seller. The provisions of 15-1-211 apply to any assessment by the department. The seller may seek review of the assessment pursuant to 15-1-211.

(b) When a deficiency is determined and the tax becomes final, the department shall mail a notice and demand for payment to the seller. Penalty and interest must be added to any deficiency assessment as provided in 15-1-216.