Best for regulars
Texas State Parks Pass
$70 for one year
Unlimited free entry for the pass holder and their guests in the same vehicle (the holder must be there), plus discounts on camping, park-store purchases, and equipment rentals.
Someone at your same address can get a second pass for $25 (buy it in person at a park). You can only buy a pass for yourself. To give one as a gift, buy a gift card instead.
The pass waives entry, but it does not guarantee a spot if the park is full - you may still need to reserve a (free, for pass holders) day pass.