You may have heard that in Ontario, buyers of used cars don’t pay sales tax to the seller. But this statement can be a bit misleading. Used car buyers in Ontario can expect to pay 13% HST when buying a used vehicle. The only difference is when you will pay it. If you are buying from a dealership, tax will be added to your bill. For a private sale, tax will be paid when registering the vehicle. To determine how much tax on a used car in Ontario you will be required to pay, you’ll want to know that you will be taxed on the purchase price or wholesale value. Whichever one is greater is what you will pay tax on.