The road narrows on both sides sign features a red warning triangle containing two inward-sloping parallel black lines.
It alerts drivers that usable carriageway space decreases ahead, which may create passing difficulties or require merging.
What this sign means
The sign warns that the road ahead narrows equally from both the left and right sides.
- Red warning triangle border
- Two symmetrical lines bending inward
- Indicates reduced carriageway width ahead
What to do when you see it
Check your mirrors and adjust your speed. Keep central within your lane and be prepared to yield space to wide or oncoming vehicles.
- Slow down to assess road clearance
- Avoid overtaking near narrowed sections
- Watch for cyclists who need extra safe clearance
How this sign is tested
DVSA theory tests evaluate your hazard recognition skills regarding spatial margins and priority rules at narrow chicanes or bridges.
Common mistakes
Maintaining high speed into narrowed sections, risking wing-mirror damage or forcing oncoming traffic to brake sharply.
Test yourself on this one
Road and traffic signs is the biggest category in the question bank with 102 questions, and signs turn up inside other categories too. Work through them free, no sign-up needed.
Practise road sign questionsFrequently asked questions
Does this sign give priority to either side?
No, this warning sign simply alerts drivers to road width reductions without establishing right of way.
Where is this sign commonly located?
It is frequently positioned ahead of narrow bridges, traffic calming chicanes, or roadwork zones.
Should I pass cyclists before the narrowing section?
Only if you can give at least 1.5 metres clearance; otherwise wait behind until the road widens.