Tex. Loc. Gov't Code § 132.004

If, for any reason, a payment by credit card is not honored by the credit card company on which the funds are drawn, the county or municipality may collect a service charge from the person who owes the fee, fine, court cost, or other charge. The service charge is in addition to the original fee, fine, court cost, or other charge and is for the collection of that original amount. The amount of the service charge is the same amount as the fee charged for the collection of a check drawn on an account with insufficient funds.