It is safe and legal to sleep in your car in most places in California, as long as you are not trust-passing, on private property or causing a disturbance. Other things to keep an eye out for are No Overnight Parking, Reserved Parking and Handicap Parking signs which could cause additional legal or towing problems.

Many California cities have specific laws regarding the homeless so make sure to do your research before hand. While you might not consider yourself homeless sleeping in your car still might fall under some of these laws. If you are worried about finding a safe and legal place to stay there are many parks, RV parks and CALTRANS rest stops that have free or cheap overnight stays.