Road signs in the United States
Road signs in the United States are, for the most part, standardized by federal regulations, most notably in the Manual on Uniform Traffic Control Devices and its companion volume the Standard Highway Signs.
Adoption and compliance
The 11th edition of the MUTCD was released on December 19, 2023. The effective date of the MUTCD was January 18, 2024, 30 days after publication. States have two years after the effective date to do one of the following options: adopt the revised MUTCD, adopt the revised MUTCD with a state supplement, or adopt a state-specific MUTCD.Eighteen states use the manual without alterations; 22 states, the District of Columbia, and Puerto Rico have adopted it in conjunction with a supplemental volume; and ten states have a state version in substantial conformance to the MUTCD. The MUTCD and SHS establish five categories of signs for road and highway use: regulatory signs, warning signs and object markers, guide signs, temporary traffic control signs, and school signs.
The list shown below does not cover all situations; the signage is from the national MUTCD unless specified.