A payment is considered to be mailed on the date the payment is postmarked.
Tex. Gov't Code § 2251.024
MAILING OF PAYMENT
Added by Acts 1993, 73rd Leg., ch. 268, Sec. 1, eff
Official source: Texas Constitution and Statutes. Reproduced from public-domain Texas statutes; confirm against the official source for the current text. Not legal advice.