Vehicle registration plates of Washington (state)

The U.S. state of Washington first required its residents to register their motor vehicles in 1905. Registrants provided their own license plates for display until 1915, when the state began to issue plates.

, plates are issued by the Washington State Department of Licensing. Front and rear plates are required for most classes of vehicles, while only rear plates are required for motorcycles and trailers.

The plates have been manufactured by incarcerated workers managed by the Washington State Department of Corrections since 1923. They are primarily produced at the Washington State Penitentiary in Walla Walla, with some also made at the Monroe Correctional Complex in Monroe.

1950 to present
In 1956, the United States, Canada, and Mexico 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 in in height by 12 in in width, with standardized mounting holes. The first Washington license plate that complied with these standards was a modification of the 1954 plate, introduced in January 1956.