Used car sales tax and dealer fees in Utah
Utah charges its combined state and local sales tax on a used car (8.45% in Salt Lake City). From a dealer it's the dealer's local rate; from a private seller it's the rate where you live, paid at the DMV. A trade-in to the selling dealer lowers the tax.
By the LotGauge team
The short answer
Utah charges its combined state and local sales tax on a used car (8.45% in Salt Lake City). From a dealer it's the dealer's local rate; from a private seller it's the rate where you live, paid at the DMV. A trade-in to the selling dealer lowers the tax.
How the rate works in Utah
Utah taxes vehicles with its regular sales and use tax: the 4.85% state rate plus local taxes, so the combined rate depends on location. Salt Lake City's combined rate is 8.45%.
When you buy from a Utah dealer, the rate is based on the dealer's location, not where you live. When you buy from a private seller (or from a dealer in another state), the rate is based on the address where you register the car.
Does a trade-in lower the tax in Utah?
Utah doesn't tax the value of your trade-in when the trade and the purchase are one transaction between the same two parties, which is the normal dealer trade-in. You pay tax only on the price minus the trade-in allowance.
Selling your old car privately and then buying from a dealer gets no credit, because those are two separate transactions.
Buying from a private seller in Utah
A private seller doesn't collect sales tax. You pay it at the Utah Division of Motor Vehicles when you title and register the car, at the rate for your address.
Bring a signed bill of sale showing the price, the VIN and any trade-in. The DMV uses it to work out the tax.
Example: a $25,000 car with a $5,000 trade-in in Salt Lake City
At Salt Lake City's rate (8.45%), the tax on a $25,000 used car from a dealer with a $5,000 trade-in is about $1,690. Without the trade-in it would be about $2,112.50, so the trade-in saves about $422.50 in tax.
8.45% of $20,000 (the $25,000 price minus the $5,000 trade-in) is $1,690. Without a trade-in it would be 8.45% of $25,000, or $2,112.50. Open this example in the calculator, then change the price, trade-in and ZIP to your own.
Dealer doc fees in Utah
On top of tax, dealers charge a documentation ("doc") fee for paperwork. The average doc fee in Utah is about $446, against a national average of $471 (CarEdge, State of Dealer Fees 2026).
Utah has no legal cap on doc fees, so the amount is up to the dealer and it's negotiable. If a dealer's fee is well above $446, ask for it to come off the price.
The LotGauge calculator checks any doc fee you enter against the Utah average. See also how to get the out-the-door price.
Related guides
How sales tax works on a used car · The trade-in tax credit by state · Private seller vs. dealer · How to read a buyer's order
Sources
Utah State Tax Commission, Publication 5: Sales Tax Information for Vehicle and Watercraft Dealers. Utah State Tax Commission, Sales and Use Tax Rates. Utah DMV, Responsibilities of Buyer and Seller. Doc fee averages: CarEdge, State of Dealer Fees 2026. Checked November 2026. Tax figures are examples for a typical dealer purchase, not tax advice; confirm the exact amount on your purchase contract.