M25
OrbitalLondon Orbital
117 miles around the capital — the UK's busiest motorway. Largely smart-managed with variable speed limits.
Motorways
The UK motorway network.
Around 2,300 miles of motorway carry roughly a fifth of all UK road traffic. Knowing the basics — signs, lane rules and smart-motorway signals — keeps you safe and out of fines.
UK motorways are designated with the prefix M (e.g. M1) or A(M) for short upgraded sections (e.g. A1(M)). The national speed limit is 70 mph for cars and motorcycles, 60 mph for cars towing trailers, and 60 mph for HGVs.
Smart motorways use overhead gantries to vary speed limits, close lanes (red X) and on some sections turn the hard shoulder into a running lane. As of 2023, new all-lane-running schemes have been paused, but existing sections remain in use.
Where & what to know
M1
StrategicLondon ↔ Leeds
193 miles. The original UK motorway, opened 1959. Smart-motorway sections between J10 and J39.
M6
StrategicRugby ↔ Carlisle
232 miles — the longest UK motorway. Connects the Midlands, North West and Scotland. Includes the M6 Toll, a 27-mile bypass of Birmingham.
M6 Toll
TollBirmingham bypass
Privately operated. £8.50 for cars (peak weekday). Pay at toll plazas — cash, card or tag. Useful for avoiding M6 congestion around Birmingham.
M4
StrategicLondon ↔ Swansea
189 miles. Connects London with the West Country and South Wales via the Severn Crossings.
M5
StrategicBirmingham ↔ Exeter
163 miles. The main route to the South West — and famously congested at summer weekends.
M8
ScotlandEdinburgh ↔ Glasgow
Central Scotland's main artery. Tight urban sections through Glasgow with frequent slip roads.
M62
Trans-PennineLiverpool ↔ Hull
Trans-Pennine motorway. Reaches the highest motorway point in England (372 m) at Windy Hill.
M11
StrategicLondon ↔ Cambridge
55 miles. Main route to Stansted Airport and Cambridge.
M40
StrategicLondon ↔ Birmingham
An alternative to the M1 via Oxford. Less congested but slightly longer.
M74 / A74(M)
ScotlandGlasgow ↔ Carlisle
Continuation of the M6 into Scotland. Free, fast, and the main route between England and Glasgow.
M20
ChannelLondon ↔ Folkestone
Main route to the Channel ports and Eurotunnel. Subject to Operation Brock contraflow during cross-Channel disruption.
Practical tips
Red X means closed
On smart motorways, a red X above a lane means that lane is closed. Driving in it can result in a £100 fine and 3 penalty points.
Hard shoulder rules
Stop on the hard shoulder only in a genuine emergency. On all-lane-running sections there is no hard shoulder — use an Emergency Refuge Area.
Average speed cameras
Many roadworks and smart sections now use average-speed cameras. The displayed limit applies until you pass the end sign — not just at the cameras.