MilesheetNobody agrees about roundabouts, and the Code is clearer than you think
Lane choice, signalling, and the spiral markings that catch out drivers who have used the same junction for years.
Roundabouts produce more confident disagreement between British drivers than any other feature of the road, which is odd, because the Highway Code is reasonably explicit.
The default lane rules
Unless signs or markings say otherwise:
- Turning left (first exit): approach in the left lane, signal left, stay in the left lane
- Straight ahead: approach in the left lane unless conditions or markings say otherwise, no signal on approach, signal left after the exit before yours
- Turning right or going full circle: approach in the right lane, signal right, and signal left after passing the exit before yours
The straight-ahead case is the contested one. A great many drivers use the right lane for straight on out of habit, and are then surprised by someone correctly in the left lane doing the same.
"Unless signs or markings say otherwise" is doing the work
On any large or busy roundabout, the markings override the defaults, and they frequently do something non-obvious — two lanes for one exit, a lane that must turn, or a spiral layout that carries you outward as you go round.
Spiral roundabouts are the ones that catch experienced drivers. Get into the correct lane on approach, follow it round, and it delivers you to your exit without lane changes. Trying to apply the default rules to a spiral produces exactly the crossing manoeuvre the design exists to prevent.
Read the road markings on approach, not the shape of the junction from memory.
The default lane and signal rules
Where no markings say otherwise:
| Taking | Approach lane | Signal on approach | Signal on exit |
|---|---|---|---|
| First exit (left) | Left | Left | Keep left signal on |
| Straight ahead | Left | None | Left, after the exit before yours |
| Right, or full circle | Right | Right | Left, after the exit before yours |
The middle row is the contested one: straight ahead is the left lane by default, not the right.
Signalling on exit
Signal left after passing the exit before the one you want. This is the single most useful thing you can do for everyone waiting to enter, and it is the thing most commonly omitted.
A driver waiting at an entry cannot read your intentions, only your indicator. Every unsignalled exit is a car that waited unnecessarily, which is a large part of why roundabouts back up.
Mini-roundabouts
Same priority rules — give way to the right — and you are expected to pass round the central marking rather than over it where the vehicle allows.
They also require a genuine attempt to give way, which at some junctions has been abandoned by mutual agreement. That agreement has no legal standing.
Why this is worth caring about at work
If you drive a van or a larger vehicle, roundabout lane discipline is where you are most likely to have a low-speed collision with a car alongside you — and the one who changed lanes is usually the one at fault.
A dashcam and a habit of following the markings rather than the memory of the junction are both cheaper than an at-fault claim on a business policy.
Sources
- The Highway Code
- The Highway Code — General rules, techniques and advice for all drivers and riders (103 to 158)
- GOV.UK — The Highway Code, road safety and vehicle rules
General road safety information, not legal advice.