Unfortunately, your car registration is not a one-time deal. In the state of California, you will need to renew your registration with the Department of Motor Vehicles (DMV) annually. It is illegal to drive with expired registration, so be sure you stay on top of your registration status. Don’t worry if you don’t know when you registration is due; the DMV sends renewal notices through the mail to make sure you know exactly when your registration is going to expire. Keep your address updated in the DMV system to ensure that you receive your notice.