As per the California Department of Motor Vehicles, providing evidence of insurance coverage (either by mail or in-person) is necessary for renewing your vehicle's registration. If your car doesn't have at least the minimum liability insurance required by the state, you must surrender its tags and registration. While regulations differ among states, the majority mandate continuous car insurance during the registration period, regardless of whether the vehicle is in use. Thus, it appears that having insurance is essential for obtaining your tags in California.