Mont. Code Ann. § 15-17-322

All money received from purchasers for delinquent taxes, penalties, interest, and costs must be deposited in the county treasury. The money received, other than costs, must be credited to the various funds to which the taxes would have originally been distributed and in the same proportion as the taxes would have originally been distributed. Any money received for costs or any money remaining after crediting the separate funds must be deposited to the credit of the county general fund.