One-way trafficUnited States

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13. One-way traffic

One-way traffic means that vehicles on a road or carriageway may travel only in one designated direction. The permitted direction is normally indicated by traffic signs, lane arrows or road markings.

Some road users, such as cyclists or public-transport vehicles, may be allowed to travel in the opposite direction when signs expressly permit it. A one-way road does not by itself determine the speed limit, priority or parking rules.

Pentagonal one-way traffic sign at North 2nd Street and East St. John Street. (San Jose, California, United States)
Wikimedia.org • Mxn • CC BY-SA
What is a one-way road?

A one-way road is a road or carriageway on which vehicles may travel only in the designated direction.

How can you recognise one-way traffic?

One-way traffic is normally indicated by a one-way sign at the entrance and a no-entry sign at the opposite end. Lane arrows and road markings may provide additional guidance.

Is a one-way sign the same as a no-entry sign?

No. A one-way sign confirms the permitted direction of travel. A no-entry sign prohibits drivers from entering from the opposite direction.

Does one-way traffic apply to the entire road?

It may apply to an entire road, one carriageway, a particular lane or only a designated section. Drivers must follow the signs and markings applying to the part of the road they use.

Can a divided road have one-way traffic on each carriageway?

Yes. On a divided road, each carriageway normally carries traffic in one direction even though the road as a whole carries traffic in both directions.

May cyclists travel against one-way traffic?

Only when traffic signs or local law expressly permit contraflow cycling. Drivers should check supplementary signs and remain alert for cyclists approaching from the opposite direction.

May buses travel against one-way traffic?

Public-transport vehicles may use a contraflow lane where signs and road markings permit it. Other drivers may not use that lane unless they are also authorised.

Does a one-way road have its own speed limit?

No. The applicable speed depends on the country, road type, surrounding area and traffic signs.

Does one-way traffic change priority at intersections?

No. Drivers must continue to follow traffic lights, priority signs and the ordinary local priority rules.

Does traffic on a one-way road always have priority?

No. The one-way designation regulates direction of travel, not priority. Traffic entering or crossing the road may still have priority under signs or local law.

Which lane should you use on a one-way road?

Follow the local lane-positioning rules, lane arrows and destination signs. Drivers commonly keep to the normal side of the road unless overtaking, turning or choosing a marked lane.

Where should you position yourself before turning?

Use the lane or side indicated for the intended direction. On many one-way roads, drivers turning towards the opposite side of the road may position themselves closer to that side before turning.

May you overtake on a one-way road?

Overtaking may be permitted where there is sufficient space and no sign or rule prohibits it. The normal overtaking side and safety requirements continue to apply unless local law provides otherwise.

May you reverse on a one-way road?

A short reversing manoeuvre may be permitted where local law allows it and it can be completed safely. Drivers must not use reversing to travel along the road in the prohibited direction.

May you make a U-turn on a one-way road?

You may not turn around and continue against the permitted direction. A U-turn may also be prohibited by signs or general traffic law.

May you park on both sides of a one-way road?

This depends on local law, signs, markings and the available width. Some countries permit parking along either side, while others retain stricter positioning rules.

Can pedestrians come from both directions?

Yes. One-way traffic restrictions normally apply to vehicles using the carriageway, not to pedestrians using pavements or other pedestrian facilities.

Should you still check both directions?

Yes. Cyclists, buses, emergency vehicles or other authorised users may approach from the opposite direction. Drivers should check both directions before turning, crossing or opening a vehicle door.

What should you do if you enter a one-way road incorrectly?

Do not continue against traffic. Stop somewhere safe without creating additional danger and follow lawful directions to leave or correct the situation. Do not reverse blindly into an intersection.

How does one-way traffic end?

The restriction may end at an end sign, an intersection, a change in road design or a sign warning that two-way traffic resumes. Follow the local signs and road layout.

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 ...