Do you need a bill of sale if you already have the title?
If the title is what proves ownership, the bill of sale can look like extra paperwork. Sometimes it is. Often it's required, and even when it isn't, it holds the facts a title has no room for: the price, the exact time the car changed hands, and what the buyer agreed to about its condition.
What each document proves
The title is a state record of ownership. When the seller signs it over and the buyer retitles the car, ownership moves. The bill of sale is the contract between the two of you. It records what was sold, for how much, when, and on what terms. One answers "who owns this car now." The other answers "what did these two people agree to."
When a state requires both
Some states require a bill of sale to title or register the vehicle, and some require it when the title doesn't show a purchase price, because the tax office needs the price to calculate sales or use tax. Others don't require it at all. Notarization is rarely required. Check your state before the sale; it takes a minute and saves a second trip to the counter. See do you need a bill of sale to register a car.
What a title has no room for
- The time of sale. The date alone isn't always enough when a toll or ticket hits the same day.
- As-is terms. The statement that the buyer accepted the car's condition with no warranty. See what selling as-is protects.
- Disclosures. Known problems you told the buyer about, in writing.
- Payment terms. Deposits, payment method, or a payment plan.
- What else was included. Spare keys, a trailer, accessories.
Many titles have a space for the purchase price and odometer reading, but very few have room for anything else.
Why sellers want one even when it's optional
From the moment you sign the title until the buyer registers the car, your name can still be attached to it. Tickets, tolls, and camera violations get mailed to the registered owner. A dated bill of sale showing the time of transfer, plus the release of liability or notice of sale your state offers, is how you prove the car was already gone. Take your plates off too, in states where they stay with the seller. See the release of liability and what to do with the plates.
Why buyers want one
The bill of sale proves the price you paid, which matters for sales tax. It's also your backup if the title paperwork goes wrong, for example when the seller signs in the wrong spot and the title has to be corrected. See a title signed in the wrong spot. A handwritten version is legal in most states if it has the same information; see handwritten bills of sale.