Texas Tax Code - TAX § 321.103. Sales Tax

(a) In a municipality that has adopted the tax authorized by Section 321.101(a), there is imposed a tax on the receipts from the sale at retail of taxable items within the municipality at any rate that is an increment of one-eighth of one percent, that the municipality determines is appropriate, that would not result in a combined rate that exceeds the maximum combined rate prescribed by Section 321.101(f), and that is approved by the voters.  The tax is imposed at the same rate on the receipts from the sale at retail within the municipality of gas and electricity for residential use.

(b) In a municipality that has adopted the additional municipal sales and use tax, the tax is imposed at any rate that is an increment of one-eighth of one percent, that the municipality determines is appropriate, that would not result in a combined rate that exceeds the maximum combined rate prescribed by Section 321.101(f), and that is approved by the voters.  The rate may be reduced in one or more increments of one-eighth of one percent or increased in one or more increments of one-eighth of one percent.  The rate that the municipality adopts is on the receipts from the sale at retail of all taxable items within the municipality and at the same rate on the receipts from the sale at retail within the municipality of gas and electricity for residential use unless the residential use of gas and electricity is exempted from the tax imposed under Section 321.101(a), in which case the residential use of gas and electricity is exempted under this subsection also.