When do you officially take possession of a new car from the dealership?

You officially take possession of a new car from the dealership when you sign the purchase agreement and make the final payment. This is usually done at the dealership, but it can also be done remotely if you are buying the car online. Once you have signed the purchase agreement and made the final payment, the dealership will give you the keys to the car and you will be able to drive it home.