Vehicle registration plates of Kansas

The U.S. state of Kansas first required its residents to register their vehicles and display license plates in 1910.

In 1956, the U.S. states and Canadian provinces came to an agreement with the Automobile Manufacturers Association that fixed the size for license plates for vehicles, except those for motorcycles, at six inches in height by twelve inches in width, with standardized mounting holes. The 1955 (dated 1956) issue was the first Kansas license plate that complied with these standards.

Letters I, O, and Q not used since 2013.

Kansas has a system of county codes used for identification of the home county of a state resident or company on license plates and state tax forms.

The codes are two letters based on the first letter of and another letter in the name of the county. There is no true convention for the selection of the letters; for example, Bourbon County is the only county that begins with "BO," yet its code is "BB." In most cases, but not all, as noted above, the only county that begins with two particular letters gets those letters. Exceptions are Decatur, Dickinson, Hodgeman, Leavenworth, Logan, McPherson (MC is used for Mitchell), Norton (NO is used for Neosho), Pawnee, and Pottawatomie.

The two-letter code began appearing on Kansas license plates in 1951. From 1930 to 1950, the code was a number based on the order a county ranked in terms of population based on the 1920 United States Census. From 1951 until 1988, the two letters were stamped on the license plate on the far left side, one letter on top of the other. Since then, the letters are on a sticker applied to the upper-left corner of the plate.

There is also a place on the address form of Kansas tax forms to place the county code.

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