Tex. Finance Code § 64.042: APPLICATION OF PREPAYMENTS TO LOAN INSTALLMENTS.

Unless otherwise agreed in writing, an association shall apply:

(1) a prepayment of principal to the final installment of the obligation until the final installment is fully paid; and

(2) additional prepayments on installments in the inverse order of their maturity.

Acts 1997, 75th Leg., ch. 1008, Sec. 1, eff. Sept. 1, 1997.