Road signs in the United States

In the United States, road signs are, for the most part, standardized by federal regulations, most notably in the Manual on Uniform Traffic Control Devices (MUTCD) and its companion volume the Standard Highway Signs (SHS).

[1] The effective date, 30 days after publication, of the MUTCD was January 18, 2024.

[3] The MUTCD and SHS establish seven categories of signs for road and highway use, as follows:[4] (The list does not cover all situations; the signage is from the national MUTCD unless specified): Regulatory signs give instructions to motorists, pedestrians, and cyclists.

Signs including Stop, Yield, No Turns, No Trucks, No Parking, No Stopping, Minimum Speed, Right Turn Only, Do Not Enter, Weight Limit, and Speed Limit are considered regulatory signs.

Some have special shapes, such as the octagon for the Stop sign and the crossbuck for railroad crossings.