Boat registration in California is completed through the California Department of Motor Vehicles (DMV). Vessel registration can be completed by mail or in-person at a boater's local DMV office. Boat registration must be completed by the driver within 120 days of residing in California. New boat registration is required for all motorized vessels, sail-powered boats over 8 feet in length, and commercial vehicles weighing a minimum of five tons or measuring at least 30 feet in length. Boat registration requirements include a boat registration fee, which must be paid when submitting a boat registration application. A bill of sale for the vessel must also be presented with the application to prove ownership. A vessel registration number (CF number) will be given to a boater once these documents are received and processed by the California DMV. Boaters must showcase their CF number on both sides or the front of their boat to show proof of registration.