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 (MUTCD) and its companion volume the Standard Highway Signs (SHS).
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.
Regulatory signs
R1 series: Stop and yield
R2 series: Speed limit
R3 series: Lane usage and turns
R4 series: Regulation of movement
R5 series: Exclusionary
R6 series: One way and divided highway
R7 series: Parking
R8 series: Parking and emergency restrictions
R9 series: Bicycles and pedestrians
R10 series: Traffic signal
R11 series: Road closed
R12 series: Weight limits
R13 series: Weigh stations
R14 series: Truck routes
R15 series: Rail and light rail
R16 series: Seat belts and headlight use
R22 series: Blasting zones
School signs
Warning signs
W1 series: Horizontal alignment
W2 series: Intersections
W3 series: Advance traffic control
W4 series: Lanes and merges
W5 series: Road width restrictions
W6 series: Divided highway
W7 series: Hills
W8 series: Pavement and roadway conditions
W9 series: Lane transitions
W10 series: Railroad crossings
W11 series: Advance warnings
W12 series: Low clearance warnings
W13 series: Advisory speeds
W14 series: Dead end streets and no passing zones
W15 series: Playgrounds
W16 series: Supplemental plaques
W17 series: Speed humps
W18 series: No traffic signs
W19 series: Freeway or expressway end signs
W20 series: Work zones
W21 series: Road work
W22 series: Blasting zones
W23 series: Slow traffic
W24 series: Lane shifts
W25 series: Oncoming traffic has extended green
W26 series: Watch for stopped traffic
Object markers
Route marker signs
M1 series: Route shields
M2 series: Junction markers
M3 series: Cardinal direction markers
M4 series: Route marker auxiliaries
M5 series: Advance turn arrow auxiliary signs
M6 series: Directional arrow auxiliary signs
M10 series: Scenic area
M11 series: National Historic Trails
Destination signs
D1 series: Destination
D2 series: Distance
D3 series: Street name
D4 series: Parking
D5 series: Rest area
D8 series: Weigh station
D10 series: Reference location
D11 series: Bicycle facility and shared-use path
D12 series: Radio, telephone and carpool information
D13 series: Crossover and freeway entrance
D15 series: Combination lane use/destination
D17 series: Truck lane and slow vehicle signs
Construction information signs
Motorist services
General information
Freeway and expressway signs
E1 series: Exit number
E2 series: Next exit
E4 series: Exit direction
E5 series: Exit gore
E6 series: Pull-through
E7 series: Post-interchange distance
E8 series: Preferential lane entrance, exit, and intermediate egress
E11 series: Panels
E13 series: Exit advisory speed
Emergency management signs
See also
Notes
References