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Traffic lightsUnited States

An introduction to the traffic rules and road signs of United States. Learn about driving, road safety and much more in our illustrated book, with answers to frequently asked questions.

For informational purposes only. Always follow official regulations. Some content and images were created with AI assistance.

Traffic signs
Traffic rules
United States

39. Traffic lights

Traffic lights use coloured lights, arrows or symbols to regulate when road users may proceed, must prepare to stop or must remain stopped. Separate signals may apply to particular directions, lanes, pedestrians, cyclists or public-transport vehicles.

A green light permits movement only when the route is clear and the movement is otherwise legal. Road users must still follow priority rules, turning restrictions, lane markings and instructions from authorised traffic controllers.

Traffic lights
Electronic traffic-control sign at Randolph Street. (United States)
Wikimedia.org • Andrew Bossi • CC BY-SA
What must a driver do at red, amber and green signals in the United States?

Signal rules are set by the state or local jurisdiction. In California, steady red means stop, steady yellow means stop if you can do so safely, and green permits proceeding when safe. Flashing red requires stopping before proceeding when safe; flashing yellow means slow down and proceed cautiously. Do not confuse a flashing signal with an ordinary green light.

🔗 dmv.ca.gov • California DMV, Driver Handbook, traffic signals

May you turn at a red traffic light in the United States?

Rules vary by state and city. California generally permits a right turn on a circular red after a complete stop and yielding, unless a sign prohibits it; it prohibits turning against a red arrow. In New York City, turning on red is prohibited unless a sign expressly permits it. Always check the applicable signs, signals and local rules.

🔗 dmv.ca.gov • California DMV, Driver Handbook, traffic signals; 🔗 dmv.ny.gov • New York DMV, Driver Manual, traffic control

Can a green light remove the need to give way to pedestrians in the United States?

No. A green signal is not a guarantee that the junction is empty. Check for people already crossing, vehicles completing a movement and any separate pedestrian, bicycle or turning signals. Do not enter if you cannot clear the junction safely.

🔗 dmv.ca.gov • California DMV, traffic-control rules; state rules vary

1 United States 2 Motorway 3 Expressway 4 Speed limit 5 Minimum speed 6 Advisory speed 7 Bike path 8 Pedestrian warning 9 Tunnel 10 Bridge 11 Speed bump 12 Toll road 13 One-way traffic 14 Slope 15 Bus lane 16 Bus stop 17 Dead end 18 Stop sign 19 Give way 20 Roundabout 21 Road narrowing 22 Pedestrian crossing 23 Railway crossing 24 Mandatory direction 25 Turn prohibition 26 School area 27 Crossing animals 28 Slippery road 29 Rockfall 30 Aircraft 31 Curve 32 Chevron 33 Wrong-way driving 34 Roadworks 35 Height limit 36 Weight limit 37 Radar speed sign 38 Selective barriers 39 Traffic lights 40 Traffic lights warning 41 Pedestrian lights 42 Road markings 43 Bike box 44 Speed feedback 45 Driving licence 46 Traffic mirror 47 Emergency telephone 48 Cycling route 49 Parking 50 No parking 51 No stopping 52 Parallel parking 53 Park and ride 54 Kiss and ride 55 Disabled parking 56 Traffic management 57 Reversing 58 U-turn 59 Carpool 60 Detour 61 Uncontrolled crossroad 62 Ramp 63 Exit 64 Horse riding 65 Emergency exit 66 Runaway truck ramp 67 Oversize load 68 City limit 69 Tourist attraction 70 Horn 71 Axle weight limit 72 Licence plate 73 Charging station 74 Flooding 75 Dip 76 Horse 77 Local traffic 78 Pedestrian 79 Cyclist 80 Motorcycle 81 Truck 82 Bus 83 Police 84 Ambulance 85 Police signals 86 Gravel road 87 Pothole 88 Median strip 89 Public property 90 Path 91 Particulates 92 Air pollution 93 Interchange 94 Rush hour 95 Filling station 96 Road code 97 Two-way traffic 98 Passing lane 99 Street gutter 100 Road debris ...