The M25 is really two motorways wearing one number. It was assembled from two separately planned schemes — Ringway 4 and the M16, or Ringway 3 — stitched together between junctions 3 and 5 and again between junctions 19 and 23. Some sections even opened under different numbers, the A405 and the A1178, before the whole thing was rebadged.
Getting there was not quick. Almost forty public inquiries took place before construction went ahead. Building ran in sections from 1975, finished ahead of schedule in October 1986, and involved planting more than 2.1 million trees and shrubs. Margaret Thatcher unveiled the completed road once the final Hertfordshire section was done.
It has never quite been a circle. The Dartford Crossing completes the orbital route but is not motorway at all — it is a trunk road designated the A282, which is why the toll applies there and nowhere else.
The M25 was also England's proving ground for traffic management: it was home to the country's first variable speed limits on motorways, between the A3 and the M4, in the early 1990s. That western stretch is still the busiest — widened to twelve lanes between junctions 14 and 15 near Heathrow in November 2005.
117 miles
Total length
J2 – J30
Junctions
4
Service stations
Explore Every M25 Junction
Every junction on the M25 has its own dedicated guide page. Find nearby fuel stations, food options, hotels, pubs, supermarkets and more — all within easy reach of the motorway.
Motorways that join the M25
| Motorway | Joins the M25 at |
|---|---|
| M20 | Junction 3 (Swanley) |
| M26 | Junction 5 (Sevenoaks) |
| M23 | Junction 7 (Merstham) |
| M3 | Junction 12 (Thorpe) |
| M4 | Junction 15 (Heathrow Airport / Slough) |
| M40 | Junction 16 (Denham) |
| M1 | Junction 21 |
| A1(M) | Junction 23 (South Mimms) |
| M11 | Junction 27 (Theydon Garnon) |
Which M25 junction for…
| Going to | Junction |
|---|---|
| Dartford | J2 (1.7 mi) |
| Orpington | J3 (3.6 mi), J4 (2.8 mi) |
| Swanley | J3 (1.3 mi), J4 (3 mi) |
| Sevenoaks | J5 (2.8 mi) |
| Westerham | J5 (3 mi) |
| Caterham | J6 (1.7 mi) |
| Gatwick Airport | J7 — via the M23 |
| Redhill | J7 (2 mi), J8 (1.9 mi) |
| Reigate | J8 (2.7 mi) |
| Ashtead | J9 (0.6 mi) |
| Leatherhead | J9 (0.6 mi) |
| Cobham | J10 (1.5 mi) |
| Addlestone | J11 (1.1 mi) |
| Chertsey | J11 (1 mi), J12 (1.3 mi) |
| Egham | J13 (1.5 mi) |
| Staines-upon-Thames | J13 (1.1 mi), J14 (3.2 mi), J15 (3.9 mi) |
| Heathrow Airport | J14, J15 — J14 for Terminals 4 and 5, J15 via the M4 for Terminals 2 and 3 |
| Gerrards Cross | J16 (2.2 mi) |
| Rickmansworth | J17 (1.4 mi), J18 (1.7 mi) |
| Kings Langley | J19 (2.5 mi), J20 (1.3 mi), J21 (2.5 mi) |
| Watford | J19 (3.1 mi), J20 (3.5 mi) |
| St Albans | J21A (3 mi), J22 (3.8 mi) |
| Potters Bar | J23 (2.2 mi), J24 (0.9 mi) |
| Chipping Barnet | J24 (2.4 mi) |
| Cheshunt | J25 (1.7 mi) |
| Waltham Cross | J25 (1.1 mi), J26 (2.5 mi) |
| Loughton | J26 (2.5 mi) |
| Epping | J27 (1.8 mi) |
| Stansted Airport | J27 — via the M11 |
| Brentwood | J28 (2 mi), J29 (3.7 mi) |
| South Ockendon | J30 (1.5 mi) |
Distances are straight-line, from the junction to the town centre.
M25 Junctions
Click a junction to explore nearby places and facilities. Each junction has its own detailed guide.