01Signing over the title
Give the buyer the valid Illinois title when you hand over the vehicle. Sign and date the Assignment of Title area on the back, and print your name as well as sign it. Fill in the odometer reading at the time of sale (and check the box if the mileage is above the odometer's mechanical limits or is not the actual mileage), the date of transfer, and the buyer's printed name and address. The title does not need to be notarized. The buyer then has 20 days to apply for a new title in their name.
Official source ↗02License plates
Illinois plates belong to the owner, not the vehicle, so they stay with you. Remove them before you deliver the car. You cannot transfer plates to the buyer. You can only move them to another vehicle you own (transfer-only fee is $25 per the Secretary of State), and the buyer must get their own plates. It is illegal to drive with someone else's plates.
Official source ↗03Telling the state you sold it
File the Seller's Report of Sale (form VSD 703) as soon as you sell. It protects you from future responsibility for the vehicle. Fill in the date of sale, the vehicle year, make and VIN, and your and the buyer's names and addresses, sign it, and mail it to Secretary of State, Vehicle Services Department, Record Inquiry Division, 501 S. Second Street, Springfield, IL 62756. The form sets no fixed number of days, only 'as soon as you sell'. It does not transfer ownership. The seller guide also mentions a Notice of Sale form attached to the bottom of some titles; mail that to the Secretary of State too. The pages reviewed did not show an online filing option.
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