Mont. Code Ann. § 15-31-503 — Deficiency Assessment -- Notice -- Penalty And Interest

15-31-503 . Deficiency assessment -- notice -- penalty and interest. (1) If the department determines that the amount of tax due is greater than the amount disclosed by the return, it shall mail to the taxpayer a notice, pursuant to 15-1-211 , of the additional tax proposed to be assessed. The taxpayer may seek review of the determination pursuant to 15-1-211 .
(2) Penalty and interest on any deficiency assessment must be calculated from the date specified in 15-31-502 for payment of the tax. Penalty and interest must be added to the deficiency as provided in 15-1-216 . A certificate by the department of the mailing of the notice specified in subsection (1) is prima facie evidence of the computation and levy of the deficiency in tax and of the giving of the notice.