What happens to my old car's insurance when I trade it in?

Your insurance does not automatically end when you trade in a car. Call your insurer to add the new vehicle and remove the old one, ideally on the day of the trade so there is no gap. You may get a refund for unused premium on the old car. If you financed the old car, confirm the dealer paid off the loan, and keep proof of the payoff. Ask your insurer whether coverage limits should change for the new car.