UK roundabouts — Highway Code rules and lane discipline

Roundabouts generate more theory-test questions, more practical-test failures and more confused Reddit posts than any other UK road feature. The Highway Code covers them in five consecutive rules — 184 to 188 — plus the 2022 hierarchy update that explicitly stops drivers overtaking cyclists in their own 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: the second or third sign on the approach usually shows lane allocation, and the first chance to slow safely is well before the give-way line.

Cancel your signal correctly. A signal that stays on when you don’t intend to turn is one of the most-cited examiner faults — 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 answer to the single most-asked roundabout question on the theory test — but only in the absence of signs, markings or lights.

Rule 186 — signals and lane choice

Rule 186 is the most-tested roundabout rule because the lane and signal differ for every exit. Use this matrix when the exit you want is …

Where there are more than three exits, the “12 o’clock” shorthand still works: anything before is a left signal on approach, anything past is a right signal.

Rule 187 — pedestrians, cyclists, horses 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.
• Cyclists and horse riders may stay in the left-hand lane all the way around the roundabout, regardless of which exit they want. Drivers must not assume a cyclist in the left lane is taking the next exit — see the 2022 H3 update below.
• Long vehicles (including those towing trailers) may straddle two lanes because of their turning circle. Give them room. They may signal differently from a car because of the path they need to follow.

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 — it covers long lorries and articulated vehicles, not regular cars or vans. Driving straight over the painted central island in a normal car 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.

Sequential (double) mini-roundabouts

Where two mini-roundabouts sit close together, treat each one separately. Apply Rule 185 (give way to the right) at the first; once you’ve cleared it, repeat the routine for the second. People who try to read both junctions as one feature get it wrong on test and in real life — including signalling once for the combined manoeuvre, which is incorrect.

Multi-lane and spiral roundabouts

Larger roundabouts (often called “magic” or spiral roundabouts) have lane markings that spiral outwards as you cross the junction. 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 + Rule 186 update

The Hierarchy of Road Users introduced on 29 January 2022 explicitly applies at roundabouts. Drivers must not attempt to overtake a cyclist within that cyclist’s lane on a roundabout, even if there appears to be space. The cyclist may be staying in the left lane on the way to taking the third exit — exactly as the cyclists’ rule allows. See the full 2022 changes summary.

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.

“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. The 2022 hierarchy makes the overtake explicitly wrong.

Sources

• GOV.UK — Highway Code: Using the road (Rules 184–188)
• GOV.UK — Highway Code: Rules for cyclists (76 — junction priority)
• GOV.UK — Highway Code: introduction (H1–H3 hierarchy)
• GOV.UK — The Highway Code: 8 changes you need to know from 29 January 2022

Highway Code excerpts are reproduced under the Open Government Licence v3.0 .