Texas car tax is going to vary because of city, county and state taxes. Each city has their own rates of taxation, as do the counties as well. The best way to figure these taxes is to go to the website for taxes in Texas. You can enter the city and county you live in and then will be given the rate of taxation for that location. This way you can figure your taxes by the amount you are giving for the vehicle multiplied by the rate of taxes then add it together for your total tax. You can figure out whether the deal you're considering on a car is as good as you originally thought. Let's say you live in Dallas and Dallas County. After you enter those into the blanks, you will get the Dallas City Tax, which is .01. Add this to the Dallas MTA tax at .01, and the state sales tax of .0625, combined together give you a tax rate of .0825. If you are buying a car for $25,000.00 multiply by 1 and then multiply by .0825. You are going to pay $2,062.50 in taxes on this vehicle. This is not including the tags and license fees. Knowing in advance what you are going to have to pay makes a lot of difference, especially if you're paying in cash or you have to pay transfer fees such as in a used vehicle.