California license plates

The U.S. state of California first required its residents to register their motor vehicles in 1905. Registrants had to provide their own license plates for display until 1914, when the state began to supply plates.

In 1956, the U.S. states and Canadian provinces came to an agreement with the American Association of Motor Vehicle Administrators, the Automobile Manufacturers Association and the National Safety Council that standardized the size for license plates for vehicles (except those for motorcycles) at 6 inches (15 cm) in height by 12 inches (30 cm) in width, with standardized mounting holes. The 1955 (dated 1956) issue was the first California license plate that complied with these standards.

License plates are currently issued by the California Department of Motor Vehicles.

California alternated issuing single-year and multi-year plates.

Some plates were revalidated for multiple years. For example, the 1947-dated plate was revalidated with metal tabs until 1950.

All base plates from 1963 to present are still valid for use, assuming the plate never left the vehicle and the vehicle maintained concurrent registration.

Modern standard issue automobile plates use a 7-digit format with a leading digit that remains constant plus a 6-digit serial starting with AAA000 and ending at ZZZ999. At that point the leading digit increases by one and the series starts over at AAA000. 7ZZZ999 was followed by 8AAA000, and should count up until the 1ABC123 series is exhausted at 9ZZZ999. At that point if the California DMV follows the precedent of reversing serial numbers at exhaustion as it has done since 1963, the next series should be in the 123ABC1 format.

Exclusions: The letters I, O, and Q are not used in the first or third alpha positions of the 7-digit alpha-numeric series.

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