Vehicle registration plates of New Hampshire

The U.S. state of New Hampshire first required its residents to register their motor vehicles and display license plates in 1905.

In 1956, the U.S. states and Canadian provinces came to an agreement with the Automobile Manufacturers Association that standardized 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 New Hampshire license plate that complied with these standards.

From 1949 to 1979, passenger plates in New Hampshire featured a two-letter code indicating the county in which the vehicle was registered, as follows:

In addition, XA-XN were used on interim plates issued to new registrants between December 1977 and December 1978, while the serial AC 000 was and still is used on sample plates.

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