Dual carriageway ends sign: what it means
Updated •5 min read
The dual carriageway ends sign warns that the road ahead stops being a dual carriageway, so traffic in both directions will soon share a single carriageway. Finish any overtaking, move back to the left-hand lane in good time and expect oncoming traffic.
A dual carriageway is a road with a central reservation separating the two carriageways, as the Highway Code defines it (gov.uk: rules 103 to 158). Where the sign appears, that separation is about to end.
What the sign looks like
The sign is a triangle with a red border and a white background. The black symbol shows two separate lanes at the bottom joining into a single road at the top.
| Detail | Dual carriageway ends sign |
|---|---|
| Shape | Triangle |
| Colours | Red border, white background, black symbol |
| Category | Warning sign |
| Official name | "Dual carriageway ends" in the Highway Code; "End of dual carriageway" in Know your traffic signs |
| What to do | Finish overtaking, keep left and expect oncoming traffic |
The Highway Code's traffic signs page lists it under warning signs, which it says are "mostly triangular" (gov.uk: traffic signs). Know your traffic signs places it in the "road narrows" part of its warning signs chapter, beside the "Two-way traffic" sign (gov.uk: Know your traffic signs, warning signs).
Our sign page for dual carriageway ends shows it alongside the other warning signs.
What you should do
The sign is a warning, so it does not set a new rule. What changes is the road, and the Highway Code's lane rules tell you how to drive on each kind:
- Before the end: on a two-lane dual carriageway you should stay in the left-hand lane, using the right-hand lane only to overtake or turn right, then move back when it is safe (rule 137). The sign is your cue to finish an overtake now, not to start one.
- On a dual carriageway with three or more lanes: you may overtake in the middle or right-hand lanes, but you should return to the middle lanes and then the left-hand lane when it is safe (rule 138).
- After the end: you are on a single carriageway with traffic coming towards you. Overtaking now means using the side of the road meant for oncoming traffic, so the general overtaking rules apply (rules 162 to 169).
- Speed: the speed limit may change too. Check the signs, and see our speed limits guide for the national limits on each type of road.
Markings you may see near the end
Know your traffic signs says hatched markings bounded by broken lines "may also be used on the approach to a central traffic island or the start of a dual carriageway" (gov.uk: Know your traffic signs, road markings). You should not enter a hatched area bounded by a broken line unless it is safe to do so. Our road markings guide explains hatched areas and chevrons.
Where a dual carriageway begins, Know your traffic signs shows separate rectangular information signs for the distance to the start, a section that begins directly ahead, and a short length of dual carriageway (gov.uk: Know your traffic signs, information signs).
How the theory test asks about it
Road signs are one of the subject areas the car theory test must cover, and Know your traffic signs and the Highway Code are two of the three books gov.uk says the questions are based on (gov.uk: revision and practice). Gov.uk does not publish the questions.
A sign question may show this triangle and ask what it means, or ask what you should do next. The lane rules matter as much as the symbol. Try our practice question on what to do after overtaking on a two-lane dual carriageway, which tests rule 137.
Our dual carriageways guide covers the rest of the rules for these roads, and the road signs guide explains how to learn signs by shape and colour.
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Start free with the theorytest.ai diagnostic to see whether road signs and lane rules are a weak area for you. theorytest.ai is independent and is not affiliated with the DVSA or the Department for Transport.
Frequently asked questions
What does the dual carriageway ends sign mean?
It warns that the road stops being a dual carriageway ahead, so traffic in both directions will share one carriageway. Finish overtaking, keep left and expect oncoming traffic.
What does the end of dual carriageway sign look like?
A red-bordered triangle with a white background. The black symbol shows two lanes at the bottom joining into a single road at the top.
Should you overtake when you see the dual carriageway ends sign?
Rule 137 says to use the right-hand lane only to overtake or turn right, then move back to the left when safe. Treat the sign as the point to finish an overtake, not to start one.
Is the dual carriageway ends sign a warning sign?
Yes. It is listed under warning signs on the Highway Code's traffic signs page, and in the warning signs chapter of Know your traffic signs.