Texas Tax Code - TAX § 152.066. Deficiency Determination;  Penalty and Interest

(a) The comptroller shall give written notice to the seller of a motor vehicle of a deficiency determination made under Section 152.044 of this code.

(b) A person who fails to pay a tax imposed by this chapter when due forfeits five percent of the amount due as a penalty, and if the person fails to pay the tax within 30 days after the day on which the tax is due, the person forfeits an additional five percent.

(c) The minimum penalty imposed by this section is $1.

(d) Except in the case of the gross receipts tax, interest begins to accrue on delinquent taxes 60 days after the day on which the joint statement was executed.  Delinquent taxes on gross rental receipts draw interest beginning 60 days from the due date.