Texas Finance Code - FIN § 306.006. Certain Authorized Charges on Commercial Loans

(1) a delinquency charge on the amount of any installment or other amount in default for a period of not less than 10 days in an amount not to exceed five percent of the total amount of the installment;  and

(2) a returned check fee in an amount that does not exceed the maximum fee authorized in Section 3.506, Business & Commerce Code, on any check, draft, order, or other instrument or form of remittance that is returned unpaid or dishonored for any reason.