VENUE.
Tex. TAX Code § 42.22.
in effect(a) Except as provided by Subsections (b) and (c), and by Section 42.221 , venue is in the county in which the appraisal review board that issued the order appealed is located.
(b) Venue of an action brought under Section 42.01 (1) is in the county in which the property is located or in the county in which the appraisal review board that issued the order is located.
(c) Venue is in Travis County if the order appealed was issued by the comptroller.