Turn prohibitionWorldwide

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.


38. Turn prohibition

A turn prohibition prevents drivers from turning in the direction indicated by a traffic sign. It may prohibit a left turn, a right turn or a U-turn at an intersection or along a specified section of road.

Drivers must continue along a permitted route and follow any lane arrows or mandatory-direction signs. A turn prohibition does not itself determine priority or speed, and any exemption for cyclists, public transport or other road users must be expressly indicated.

Turning left prohibited for vehicles above 6 tonnes. (Haute-Savoie, France)
Wikimedia.org • Marc Mongenet • CC BY-SA
What is a turn prohibition?

A turn prohibition prevents drivers from making a particular turn or change of direction indicated by a traffic sign.

How can you recognise a turn-prohibition sign?

It is commonly a circular sign with a red border showing a crossed or barred turning arrow. The arrow indicates the movement that is prohibited.

What does a no-left-turn sign mean?

It prohibits drivers from turning left at the location or intersection to which the sign applies.

What does a no-right-turn sign mean?

It prohibits drivers from turning right at the location or intersection to which the sign applies.

What does a no-U-turn sign mean?

It prohibits drivers from turning around to travel in the opposite direction.

Is a prohibited turn the same as a mandatory direction?

No. A prohibition sign identifies a movement that may not be made. A mandatory-direction sign identifies the direction or directions that must be followed.

Is a turn prohibition the same as a no-entry sign?

No. A turn prohibition prevents a particular approach from turning into a road. A no-entry sign prohibits vehicles from entering the road from the direction where it is displayed.

Is a turn prohibition the same as one-way traffic?

No. A one-way rule controls the permitted direction along a road. A turn prohibition controls a particular movement at or near an intersection.

When does a turn prohibition apply?

It may apply at the sign, at the next intersection or throughout a stated section. Drivers must follow the sign design and the rules of the country concerned.

Can a turn prohibition be announced in advance?

Yes. An advance sign or supplementary distance panel may warn drivers that the prohibited turn is farther ahead.

Can the sign apply to only one lane?

Yes. A sign positioned above or clearly associated with one lane may apply only to drivers using that lane.

Do lane arrows also restrict turning?

Yes. Drivers must choose the correct lane and follow one of the directions displayed by its legally binding arrows.

Does a green traffic light permit a prohibited turn?

No. A green light permits traffic to proceed, but drivers must still respect turn prohibitions, lane arrows and other regulatory signs.

Does a turn prohibition change priority?

No. Drivers making another permitted movement must still follow traffic lights, priority signs and the ordinary rules concerning pedestrians, cyclists and other vehicles.

Does a turn prohibition impose a speed limit?

No. The applicable general, zonal or posted speed limit remains in force.

Must you use an indicator for a permitted turn?

Yes, where local law requires it. Signal early enough to communicate your intention and stop signalling after completing the movement.

Does signalling make a prohibited turn legal?

No. An indicator communicates an intention but cannot authorise a movement prohibited by a traffic sign.

May cyclists be exempted?

Yes. A supplementary sign may allow cyclists or other specified road users to make a turn that remains prohibited for general traffic.

May buses or taxis be exempted?

Public transport, taxis or other authorised vehicles may be exempted where a supplementary sign or local rule expressly permits the movement.

Does a no-left-turn sign also prohibit a U-turn?

Not universally. Some countries treat these as separate prohibitions. Drivers must check whether a separate no-U-turn sign or general rule applies.

May you turn into a driveway before the prohibited intersection?

This depends on the exact legal scope of the sign. A sign applying specifically to the next intersection may not regulate an earlier property entrance, but another sign or road marking may still prohibit the movement.

May you reverse to avoid the turn prohibition?

No. Do not reverse through traffic or into an intersection to evade the sign. Continue along a permitted route and change direction later where it is legal and safe.

What should you do after entering the wrong lane?

Follow the movement permitted from that lane. Do not turn suddenly across another lane or ignore the sign; continue and choose another legal route.

Can a temporary turn prohibition be binding?

Yes. Properly placed temporary signs near roadworks, incidents or events must be obeyed.

Do instructions from an authorised officer override the sign?

Yes. Follow instructions from an authorised traffic officer even when they differ from the displayed turn prohibition.

1 Worldwide 2 Motorway 3 Expressway 4 Residential area 5 Built-up area 6 Zone 7 Speed limit 8 Minimum speed 9 Advisory speed 10 Footpath 11 Bike path 12 Shared-use path 13 Separated path 14 Pedestrian warning 15 Tunnel 16 Bridge 17 Cycling street 18 Pedestrian zone 19 Speed bump 20 Toll road 21 Customs 22 One-way traffic 23 Quay 24 Slope 25 Bus lane 26 Bus stop 27 Dead end 28 Stop sign 29 Give way 30 Roundabout 31 Priority road 32 Road narrowing 33 Priority over oncoming traffic 34 Give way to oncoming traffic 35 Pedestrian crossing 36 Railway crossing 37 Mandatory direction 38 Turn prohibition 39 School area 40 Overtaking 41 Crossing animals 42 Slippery road 43 Rockfall 44 Aircraft 45 Curve 46 Chevron 47 Wrong-way driving 48 Roadworks 49 Crosswind 50 Height limit 51 Width limit 52 Length limit 53 Weight limit 54 Radar speed sign 55 Selective barriers 56 Low-emission zone 57 Intersection direction sign 58 Priority at the next junction 59 Traffic lights 60 Traffic lights warning 61 Pedestrian lights 62 Road markings 63 All-way stop 64 Junction layout 65 Climbing lane 66 Bike box 67 Left-hand traffic 68 Speed feedback 69 Driving licence 70 Location marker 71 Road number 72 Countdown markers 73 Public toilet 74 Rest area 75 Traffic mirror 76 Emergency telephone 77 International border 78 Pedestrian underpass 79 Cycling route 80 End of restriction 81 Parking 82 No parking 83 No stopping 84 Parallel parking 85 Park and ride 86 Kiss and ride 87 Alternate-side parking 88 Parking meter 89 Parking disc 90 Disabled parking 91 Traffic management 92 Merging 93 Reversing 94 U-turn 95 Carpool 96 Traffic jam 97 Detour 98 Uncontrolled crossroad 99 Road surface 100 Advisory cycle lane ...