The U.S. state of Oklahoma first required its residents to register their motor vehicles and display license plates in 1915. As of 2024, plates are issued by Service Oklahoma. Only rear plates have been required since 1944.
Prior to July 1, 2019, plates belonged to the car, not the owner. As a result of lost turnpike toll revenue and law enforcement having trouble tracking vehicle owners, the law was changed, meaning plates now belong to vehicle owners and can be transferred from a previous vehicle to a new vehicle.
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 in height by in width, with standardized mounting holes. The 1955 (dated 1956) issue was the first Oklahoma license plate that complied with these standards.
The order of the numeric county codes used from 1952âÂÂ61 was based on the populations of each county according to the 1950 United States census, and the order of the codes used in 1962 was based on the populations of each county according to the 1960 census, in 2009 county codes were reintroduced on month stickers. As of 2025, both the county abbreviated and the month only abbreviation is currently being used. However, as of 2024, the county abbreviated decal is no longer being issued by the state.