UK roundabouts — Highway Code rules and lane discipline

A roundabout asks you to settle lane, signal and priority in the same few seconds, and getting any one of them wrong shows up on the theory test and on the practical. The Highway Code covers them in seven consecutive rules — 184 to 190 — plus the 2022 update that tells drivers not to overtake a cyclist within that cyclist’s lane. Every rule and the lane discipline that flows from it, below.

When reaching the roundabout you should give priority to traffic approaching from your right, unless directed otherwise by signs, road markings or traffic lights.

Rule 184 — approach

On approaching a roundabout, apply the Mirrors – Signal – Manoeuvre (MSM) routine at every stage and decide as early as possible which exit you need to take. Look well ahead: lane allocation is signed on the approach, and the first chance to slow safely comes well before the give-way line.

Cancel your signal correctly. A signal left running when you don’t intend to turn tells the driver behind that you are leaving at an exit you are not — and on the theory test it’s a familiar wrong-answer trap.

Rule 185 — priority

Give priority to traffic approaching from your right. The rule has one universal override: signs, road markings or traffic lights take precedence over the general right-of-way rule.

• If the roundabout has traffic lights, treat the lights as you would at any junction.
• If road markings direct otherwise (e.g. arrows pointing across), follow the markings even if it feels counter-intuitive.
• If signs indicate otherwise (some larger junctions have non-standard priority), follow the signs.

“Give priority to traffic from your right” is the default answer — but only in the absence of signs, markings or lights. What it resolves to when the road on your right is empty, and what happens when two vehicles reach the give-way line together, is in When two vehicles arrive together below.

Rule 186 — signals and lane choice

Rule 186 is the one to memorise, because the lane and the signal differ for every exit. Use this matrix when the exit you want is …

Rule 186 itself uses the phrasings “first exit to the left” for left turns, “any intermediate exit” for the straight-on or middle case, and “an exit to the right or going full circle” for right turns — plus one instruction for the biggest junctions: where there are more than three lanes at the entrance, use “the most appropriate lane on approach and through it”. The 12 o’clock framing is a memory aid that maps onto those three cases.

Which lane: how to decide

Rule 184 answers this before you reach the give-way line, and it puts the junction in front of you ahead of any general rule.

On approaching a roundabout take notice and act on all the information available to you, including traffic signs, traffic lights and lane markings which direct you into the correct lane.

So the order of decision is: what this roundabout tells you first, what Rule 186 tells everybody last. Work down the list and stop at the first step that gives you an answer.

1. A sign or a marking that gives an order. Circles give orders, and a blue circle — “turn left ahead”, “keep left”, an arrow to be followed — gives a mandatory instruction. Painted arrows do the same job at some junctions: one kind shows the lanes appropriate for each movement, the other states compulsory movements, and those apply either to one lane or to every vehicle on the approach. Where the marking states a compulsory movement, the lane has made the choice for you.
2. Lane allocation shown on the approach. A map-type advance direction sign draws the junction layout, and a separate lane-allocation sign showing the appropriate lanes for each turn is sometimes used alongside it or instead of it. Both give you the answer while you can still change lanes comfortably.
3. The arrows and destination markings in the lanes. Painted lane arrows show the appropriate lane for each movement at the junction ahead, and some approaches name the destination in the lane instead. This is the most specific instruction you get, and the last one you see.
4. Rule 186’s three cases. The first exit, any intermediate exit, or an exit to the right and going full circle. Every one of them is written “unless signs or markings indicate otherwise”, which is why it comes after steps 1 to 3 rather than before them.
5. An unmarked approach. Rule 160 is the fallback: keep to the left, unless road signs or markings indicate otherwise, the exceptions being when you want to overtake, turn right, or pass parked vehicles or pedestrians in the road. That is where the left-hand lane default for an intermediate exit comes from, and why the right-hand lane belongs to exits to the right and to going full circle.

Some of that is advice and some of it is law. A painted line or arrow is itself a traffic sign in law — the statutory definition reaches “any line or mark on a road” that conveys a requirement, restriction or prohibition — and a driver who fails to comply with the indication given by a lawfully placed sign of the prescribed type is guilty of an offence. That is the difference between an arrow you should follow and an arrow you must.

When the arrows and the clock face disagree

The clock face is a teaching aid, not Code text. The Code sorts exits into three cases — the first exit to the left, any intermediate exit, and an exit to the right or going full circle — and the 12 o’clock line is a quick way of deciding which case you are in on a roundabout whose arms are evenly spaced. On a skewed junction it stops working: a second exit can sit past the top of the roundabout, and a third can sit before it.

When that happens, read the arrows instead of the clock. The arrows describe which exits each lane serves at this roundabout, which is the thing the clock face is only estimating. Two habits settle almost every case:

• Read every arrow across the approach, not only the one in your lane. If the left-hand lane is arrowed left-only, your second exit is served by a different lane, and the place to be in it is the approach.
• Treat a double-headed arrow as information, not a contradiction. It marks a lane from which two different movements may be made, or a lane that divides into two or more lanes further on.

With no arrows and no lane sign, the geometry decides: if the exit takes you round to the right of straight ahead, it is an exit to the right, so approach in the right-hand lane, signal right, and signal left once you have passed the exit before the one you want.

If you end up in the wrong lane

Take the exit your lane serves and come back round. Rule 186 has you stay in your lane until you need to alter course to leave, and Rule 187 warns every other driver about traffic straddling lanes or positioned incorrectly — which is exactly what a late correction looks like from behind. If you do have to change lane, the standard is the same one examiners apply on the practical test.

If you need to change lane, first use your mirrors and if necessary take a quick sideways glance to make sure you will not force another road user to change course or speed. When it is safe to do so, signal to indicate your intentions to other road users and when clear, move over.

Counting the exits

Exit numbers only work if everyone counts the same way, and Rule 186 turns the count into an instruction: you signal left after you have passed the exit before the one you want. Miscount by one and you signal into somebody else’s gap.

Count clockwise from the road you arrive on. The first road leaving the roundabout after your own approach is exit 1, whether it is a dual carriageway or an unnamed lane to a village. The road you came in on is not counted.

• Get the count from the map-type sign before you arrive. A map-type sign shows the junction layout and is the type commonly used for roundabouts, with its own symbol for mini-roundabouts. The width of each route symbol tells you what the arm is: wide for primary routes and motorways, medium for numbered A and B roads, narrow for local roads without numbers. The narrow one is the arm people forget to count.
• Don’t count arms off a stack-type sign. A stack-type sign lists the directions at the junction ahead but not the road layout, and where a side road is minor the ahead direction may not be shown on it at all.
• A segregated left-turn lane is still exit 1. Some conventional roundabouts have a left-turn lane where drivers do not give way to traffic on the roundabout, separated by a solid island or by chevrons. It takes you to the first exit without ever joining the circulating carriageway. Rule 185 makes the same point from the other direction: check whether the road markings allow you to enter the roundabout without giving way, and if they do, still look right before you join.
• On a spiral roundabout, the lane does the counting. Choose it on the approach and follow it — see Multi-lane and spiral roundabouts below.

Worked through on a four-arm roundabout where you want exit 3, which sits past the top of the junction: unless the signs or markings say otherwise it is an exit to the right, so right-hand lane and a right signal on the approach, keep right on the roundabout, hold that through exit 1, pass exit 2, and only then signal left and change course to leave by exit 3. The wording behind that sequence is Rule 186 in the Highway Code itself.

Rule 187 — extra care for pedestrians, motorcyclists and long vehicles

Rule 187 lists the categories of road user that need extra care at every roundabout:

• Pedestrians who may be crossing the approach and exit roads. Give them time.
• Traffic crossing in front of you on the roundabout, especially vehicles intending to leave by the next exit, and traffic which may be straddling lanes or positioned incorrectly.
• Motorcyclists — small profile, easy to miss in a quick mirror check.
• Long vehicles (including those towing trailers) may take a different course or straddle lanes, approaching or on the roundabout, because of their length. Give them room, and watch out for their signals — the path they need dictates them.

Cyclists, horse riders and horse-drawn vehicles on the roundabout

Rule 186 closes with the paragraphs that most often catch drivers out: “Cyclists, horse riders and horse drawn vehicles may stay in the left-hand lane when they intend to continue across or around the roundabout and should signal right to show you they are not leaving the roundabout.” That much has been in the Code for years. What the January 2022 update added is the instruction sitting above it — give priority to cyclists on the roundabout, “do not attempt to overtake them within their lane”, allow them to move across your path — together with the warning not to cut across them as you enter.

So never read a cyclist in the left-hand lane as taking the next exit. The right-arm signal is the cue that they are staying on the roundabout. See the 2022 update below.

Rule 188 — mini-roundabouts

Mini-roundabouts are approached and treated like normal roundabouts. Two specific rules apply:

All vehicles MUST pass round the central markings except large vehicles which are physically incapable of doing so.

The “physically incapable” exemption is narrow, and this is one of the roundabout rules that carries a MUST. Rule 188 is backed by the Road Traffic Act 1988 section 36, so driving straight across the painted central markings of a mini-roundabout in a car or a van is an offence.

Avoid making a U-turn at a mini-roundabout if possible. Drivers behind you have very little time to see what you’re doing.

Priority at a mini-roundabout is not simply Rule 185 restated either. The sign carries the give-way in law, and the regulations behind it add a requirement that decides most standoffs — see When two vehicles arrive together below.

Rule 189 — double mini-roundabouts

Where two mini-roundabouts sit close together, Rule 189 is one sentence long and leaves nothing to interpretation.

At double mini-roundabouts treat each roundabout separately and give way to traffic from the right.

Clear the first, then run the whole routine again for the second. Reading both junctions as one feature — and signalling once for the combined manoeuvre — is what goes wrong on test and on the road.

Rule 190 — multiple roundabouts

At some complex junctions there is a series of mini-roundabouts, one at each intersection. Treat each mini-roundabout separately and follow the normal rules. This is the layout the nickname “magic roundabout” belongs to — a ring of mini-roundabouts at a single junction, not a roundabout with spiral lane markings.

Multi-lane and spiral roundabouts

Larger roundabouts often carry lane markings that spiral outwards as you cross the junction, feeding each lane to its own exit. The rule is: follow your lane — don’t change lanes on the roundabout itself unless arrows direct otherwise. The painted arrows tell you which exit each lane allows; an early lane choice is what protects you.

The 2022 hierarchy change — Rule H3 and the Rule 186 update

The Hierarchy of Road Users introduced on 29 January 2022 names the roundabout directly: Rule H3 tells drivers to stop and wait for a safe gap in the flow of cyclists, including cyclists travelling around a roundabout. Rule 186 goes further and tells you not to attempt to overtake a cyclist within that cyclist’s lane, even where there appears to be space. The cyclist may be staying in the left lane on the way to the third exit — exactly as the Code allows.

Neither is worded as a MUST, so neither is an offence in itself. Both are still what the theory test marks as correct, and the Code can be used in evidence in court proceedings — advisory rules included. See the full 2022 changes summary.

When two vehicles arrive together

Rule 185 settles priority in one line, and the line is about traffic, not about arms of the junction. Two things follow from that, and between them they end most of the arguments.

• An empty road on your right is not a reason to wait. If nothing is approaching from your right there is nothing to give priority to. Go — after the rest of Rule 185, which asks you to look right before joining, to watch the road users already on the roundabout, and to look forward in case the vehicle in front of you has not moved off.
• An empty arm on your right is not a reason to go, either. A car that entered two arms further round is still traffic approaching from your right by the time it reaches you. Which arm it started from is irrelevant; where it is now is the whole test.

watch out for all other road users already on the roundabout; be aware they may not be signalling correctly or at all

A give-way line is also not a stop line. The MUST-stop rule belongs to a junction with a ‘Stop’ sign and a solid white line across the road — Rule 171 — and the broken lines at a roundabout entry are not that. Nothing obliges you to come to a halt at them when the roundabout is genuinely clear. It is a judgement you have to be right about, which is why the observation matters more than the stop.

Mini-roundabouts: the same priority, written as a MUST

At a mini-roundabout the give-way stops being advice. The mini-roundabout sign sits among the regulatory signs — the ones giving orders — and the official sign catalogue names it in full: mini-roundabout (give way to traffic from the immediate right).

A mini-roundabout is normally found on a road with a speed limit of 30 mph or less. It should be treated the same as a conventional roundabout. You must give way to traffic from the right, and keep to the left of the white circle unless the size of your vehicle or the junction layout makes driving over it unavoidable.

The regulations that prescribe the sign set out three requirements for a vehicle entering the junction. Give priority to vehicles coming from the right — at the give-way marking, or at the junction itself if no marking is visible. Keep to the left of the white circle, unless the size of the vehicle or the layout of the junction makes that impracticable. And do not proceed past the circle in a manner, or at a time, likely to endanger any person or to cause another driver to change speed or course in order to avoid an accident. Section 36 of the Road Traffic Act 1988 is what gives those requirements teeth, as it does for every other sign whose indication is a statutory prohibition, restriction or requirement.

That third requirement is the one nobody quotes and the one that actually settles a standoff. It never says who goes first. It says that whoever moves in a way that forces somebody else to brake or swerve is the one in the wrong — regardless of which arm they came from, and regardless of who felt they had waited longest.

The four-way standoff, and what the Code does not say

Nothing in the Highway Code names who goes first when three or four vehicles reach a roundabout at the same moment and none of them is established on it. There is no tiebreaker, no seniority, no rule about the wider road or the busier road or the vehicle already indicating. That absence is the answer, and it is worth knowing rather than guessing at, because every confident-sounding alternative you hear at a junction is a local custom rather than a rule.

The Code is comfortable with junctions that have no priority — it names them directly, and it answers them with caution rather than a hierarchy.

in side roads and country lanes look out for unmarked junctions where nobody has priority

So work it in this order, and the deadlock usually turns out not to exist.

1. Anyone past the give-way line is established. They are now traffic on the roundabout, which arrives at somebody from the right. A true standoff only exists while every vehicle is still behind its own line.
2. Take the arms in pairs. Vehicles rarely arrive from every arm at once. If one of the two is to the other’s right, Rule 185 has already decided it — and at a mini-roundabout it has decided it in law.
3. If nothing decides it, one driver moves. Rule 170 sets the standard for emerging: look all around, and do not cross or join a road until there is a gap large enough to do so safely. The first driver who can take the junction without forcing anybody to change speed or course should take it, promptly and slowly. Four drivers each edging forward half a car length is what turns a two-second junction into a minute of shuffling.
4. Then hold back for whoever went. Rule 147 asks you to slow down and hold back if a road user pulls out into your path at a junction and to allow them to get clear, to be understanding if other road users cause problems, and to be patient — anyone can make a mistake.

One habit to drop: do not flash somebody through, and do not treat a flash as your cue.

Never assume that flashing headlights is a signal inviting you to proceed. Use your own judgement and proceed carefully.

Rule 110 is the other half of it: only flash to let other road users know that you are there, not to convey any other message. The driver you wave out cannot see what you can see, and if it goes wrong the Code has already told them not to rely on you.

An indicator is not priority

Four rules say this, in four different places, which is a fair measure of how often it goes wrong.

Remember that signalling does not give you priority.

• Rule 104 — watch out for signals given by other road users and proceed only when you are satisfied that it is safe, and be aware that an indicator on another vehicle may not have been cancelled.
• Rule 170 — do not assume, when waiting at a junction, that a vehicle coming from the right and signalling left will actually turn. Wait and make sure.
• Rule 185 — road users already on the roundabout may not be signalling correctly, or at all.

The practical version: a left indicator on the car to your right is a hint, not a green light. What converts it into one is the car actually slowing and turning in. Wait for the wheels, not the lamp. Mini-roundabouts make the hint weaker still — Rule 188 points out that there is less space to manoeuvre and less time to signal, so on the smallest junctions a correct signal may never appear even from a driver doing everything else right. And a cyclist signalling right in the left-hand lane means the opposite of what a car’s right signal means: they are staying on the roundabout, not offering you a gap.

Common test questions and the answers

“Who has priority at a mini-roundabout?”

Traffic from the right has priority — the same as a normal roundabout. The smaller scale doesn’t change Rule 185. What does change is the force of it: the mini-roundabout sign carries the give-way as a legal requirement rather than as advice.

“The road on my right is completely empty. Do I have to stop at the give-way line?”

No. Rule 185 asks you to give priority to traffic approaching from your right, and if there is none there is nothing to give way to. Stopping is compulsory at a ‘Stop’ sign with a solid white line across the road (Rule 171), which is a different marking from the broken give-way lines at a roundabout. Look right before you join anyway, and read the roundabout itself rather than the arm — traffic that entered further round arrives from your right too.

“The car on my right is signalling left. Can I pull out?”

Not on the signal alone. Rule 170 tells you not to assume that a vehicle coming from the right and signalling left will actually turn — wait and make sure. Rule 103 is blunter: signalling does not give you priority. And Rule 104 names the usual cause — the indicator may simply not have been cancelled from the last turn.

“Four cars arrive at a mini-roundabout at the same time. What does the Highway Code say?”

Nothing, and that is the answer. No rule ranks simultaneous arrivals when none of the vehicles is established on the roundabout. What still applies is everything that stops it becoming a collision: give priority to anyone already past their give-way line, do not enter in a way that forces another driver to change speed or course, and be patient. One driver moving decisively clears it; four drivers edging forward does not.

“I’m taking the third exit. When do I signal left?”

After you pass the exit immediately before yours. Signal too early and the driver behind thinks you’re leaving at the wrong exit; signal too late and the driver behind has no warning.

“The right lane is empty and the left lane is busy. Can I take the second (straight-on) exit from the right lane?”

Only if signs or arrows explicitly allow it. The default for a straight-ahead exit is the left lane. Some larger roundabouts mark the right lane as straight-on permitted (look for arrows on approach) — but assume left-lane unless the markings say otherwise.

“There’s a cyclist on the roundabout in the left lane. I want to take the second exit. What should I do?”

Wait behind them rather than overtake. The cyclist may be going to the third or fourth exit in the left lane, which the Code expressly permits, and Rule 186 tells you not to overtake them within their lane.

“There are no arrows and no lane sign. Which lane do I take for the second of four exits?”

The left-hand lane, and a left signal once you have passed exit 1. An unmarked approach falls back to Rule 160 — keep to the left unless road signs or markings indicate otherwise — and at an intermediate exit Rule 186 says you should not normally need to signal on the approach at all.

“The left-hand lane is marked left-only and my exit is the second one. Where do I go?”

Not the left-hand lane. The arrows describe which exits each lane serves at that particular roundabout, and they displace the general rule — Rule 186 says so three times, once for each of its three cases. Read the arrows across the whole approach, pick the lane whose arrow includes your exit, and be in it before the give-way line. If you only spot it once you are committed, take the first exit and come back rather than cut across.

Where this shows up in revision

Roundabout priority, give-way markings and signalling sit in the Rules of the road revision topic. The multiple-choice questions are based on three books, the first two of which are the ones quoted all the way down this page: The Highway Code and Know your traffic signs. Work the 14 DVSA topics, read Rules 103, 104, 146, 147, 170–172 and 184–190 in the Highway Code, see how the priority pattern gets written into exam wording in trick questions, and sit a full mock theory test under the real timer. It is free to get started.

Sources

• GOV.UK — Highway Code: Using the road (Rules 160, 170–172, 184–190)
• GOV.UK — Highway Code: general rules, techniques and advice for all drivers and riders (Rules 103, 104, 110, 111, 133, 144, 146, 147)
• GOV.UK — Highway Code: Rules for cyclists (Rules 78–80 — roundabouts)
• GOV.UK — Highway Code: introduction (H1–H3 hierarchy)
• GOV.UK — Highway Code: traffic signs — signs giving orders
• GOV.UK — Know your traffic signs: the signing system
• GOV.UK — Know your traffic signs: regulatory signs — blue circles giving a mandatory instruction
• GOV.UK — Know your traffic signs: road markings — traffic lanes at junctions, roundabout markings
• GOV.UK — Know your traffic signs: direction signs on all-purpose roads — map-type and stack-type signs
• legislation.gov.uk — Road Traffic Regulation Act 1984, section 64 (traffic signs include lines and marks on a road)
• legislation.gov.uk — Traffic Signs Regulations and General Directions 2016, Schedule 9, Part 7 — requirements conveyed by the mini-roundabout (priority to right) sign, para 5
• legislation.gov.uk — Traffic Signs Regulations and General Directions 2016, Schedule 9, Part 6 — regulatory road markings, give-way and roundabout lines
• legislation.gov.uk — Road Traffic Act 1988, section 36 (drivers to comply with traffic signs)
• GOV.UK — The Highway Code: 8 changes you need to know from 29 January 2022
• GOV.UK — Theory test: revision and practice

Highway Code and Know your traffic signs excerpts are reproduced under the Open Government Licence v3.0.