The official DVSA guide to driving states:
Because of the volume of traffic on three-lane motorways, many are being widened to four or more lanes in each direction.
Keep to the left-hand lane unless there are slower vehicles ahead – it’s possible to stay in the centre or outer lanes while you’re overtaking a number of slower-moving vehicles, but don’t stay in these lanes
- longer than you have to
- if you’re delaying traffic behind you.
Drivers of large goods vehicles, buses, coaches or any vehicle towing a trailer aren’t allowed to use the extreme right-hand lane of a motorway with more than two lanes, unless one or more lanes are temporarily closed.
Don’t stay in an overtaking lane longer than it takes you to move out, overtake and move in again safely. Make sure you don’t block traffic that’s not allowed to use the outer lane.
