← General rules, techniques and advice for all drivers and riders
Rule 138: Three-lane dual carriageways
Advice, not law
Multi-lane carriageways (rules 133 to 143)
On a dual carriageway with three or more lanes, you may use the middle lanes or the right-hand lane to overtake but you should return to the middle lanes and then the left-hand lane when it is safe to do so.
Advice, not law. This rule is not written in capitals, so breaking it is not an offence in itself — but it can still be used in evidence in court to establish liability. The rules that say MUST or MUST NOT are the ones backed by law.
5 theory test questions on this rule
From the DVSA revision question bank. These are not the questions asked in the real theory test. Each one shows the answer, the explanation, and our own note on why every other option is not it.
Car
Lorry & Bus (LGV/PCV)
- You're driving in the left-hand lane on a three-lane motorway. What should you check for before moving into the middle lane to overtake a slower vehicle? The road
- You're driving a lorry with a maximum authorised mass of more than 7.5 tonnes along a three-lane motorway. When may you use the right-hand lane? Vehicle weights and dimensions
- You want to turn right at a roundabout marked with 2 right-turn lanes. What should you do if there's sufficient room for your vehicle in either lane? Restricted view