41 roads, measured between 1 May 2026 and 15 June 2026
The slowest roads in England, ranked
The M18 falls furthest. At its worst hour, Friday at 15:00, it averages 44 mph, about 36% below the speed it runs at when it is clear. Every road below is ranked the same way, measured between 1 May 2026 and 15 June 2026 rather than estimated.
Ranked by how far each road falls
Worst hour, 06:00 to 22:00| # | Road | Worst hour | Speed then | Below its normal | Sensors |
|---|---|---|---|---|---|
| 1 | A45 | Thursday 08:00 | 30 mph | 46% | 2 thin |
| 2 | A38 | Tuesday 07:00 | 40 mph | 39% | 1 thin |
| 3 | M18 | Friday 15:00 | 44 mph | 36% | 5 |
| 4 | M32 | Tuesday 08:00 | 36 mph | 35% | 5 |
| 5 | M60 | Wednesday 08:00 | 40 mph | 35% | 12 |
| 6 | M621 | Wednesday 16:00 | 46 mph | 27% | 5 |
| 7 | M61 | Wednesday 07:00 | 49 mph | 26% | 5 |
| 8 | A1 | Friday 14:00 | 47 mph | 26% | 5 |
| 9 | M25 | Friday 16:00 | 46 mph | 26% | 62 |
| 10 | M11 | Friday 16:00 | 44 mph | 25% | 24 |
| 11 | A2 | Tuesday 07:00 | 45 mph | 25% | 12 |
| 12 | M62 | Tuesday 07:00 | 50 mph | 24% | 12 |
| 13 | M42 | Tuesday 08:00 | 48 mph | 22% | 12 |
| 14 | M5 | Friday 14:00 | 49 mph | 22% | 12 |
| 15 | M55 | Tuesday 08:00 | 47 mph | 21% | 5 |
| 16 | M6 | Wednesday 08:00 | 50 mph | 21% | 12 |
| 17 | M27 | Tuesday 07:00 | 51 mph | 21% | 12 |
| 18 | M56 | Friday 16:00 | 53 mph | 20% | 5 |
| 19 | A14 | Wednesday 17:00 | 44 mph | 20% | 5 |
| 20 | A20 | Tuesday 08:00 | 29 mph | 18% | 4 thin |
| 21 | M4 | Tuesday 07:00 | 52 mph | 17% | 38 |
| 22 | M54 | Thursday 13:00 | 49 mph | 16% | 5 |
| 23 | A27 | Thursday 17:00 | 54 mph | 15% | 5 |
| 24 | A42 | Tuesday 07:00 | 54 mph | 15% | 5 |
| 25 | M66 | Thursday 16:00 | 53 mph | 15% | 7 |
| 26 | M67 | Wednesday 07:00 | 48 mph | 14% | 5 |
| 27 | A1(M) | Friday 11:00 | 52 mph | 14% | 11 |
| 28 | M602 | Tuesday 08:00 | 53 mph | 13% | 8 |
| 29 | M1 | Tuesday 08:00 | 53 mph | 12% | 22 |
| 30 | M20 | Thursday 16:00 | 50 mph | 12% | 19 |
| 31 | A3 | Thursday 13:00 | 60 mph | 10% | 5 |
| 32 | M3 | Tuesday 08:00 | 57 mph | 9% | 12 |
| 33 | M180 | Tuesday 10:00 | 63 mph | 8% | 4 thin |
| 34 | M40 | Thursday 15:00 | 54 mph | 8% | 16 |
| 35 | M2 | Thursday 15:00 | 50 mph | 8% | 5 |
| 36 | M45 | Tuesday 21:00 | 48 mph | 8% | 3 thin |
| 37 | M23 | Thursday 09:00 | 56 mph | 8% | 12 |
| 38 | M65 | Tuesday 07:00 | 58 mph | 8% | 5 |
| 39 | A11 | Monday 07:00 | 62 mph | 7% | 3 thin |
| 40 | M69 | Wednesday 10:00 | 52 mph | 7% | 5 |
| 41 | M49 | Friday 12:00 | 63 mph | 6% | 5 |
6 of these roads carry fewer than 5 sensors and are marked thin. They are ranked with the rest because the reading is still real, but they are left out of the answers at the top of this page: a road measured at two points cannot fairly be called the worst in the country. Read the speed and the percentage together. The percentage is how far a road falls below its own free-flowing speed, not how fast it is. A road that never moves quickly has little room to fall and will sit low in this ranking while still being slow to drive. That is why the speed at the worst hour is printed next to it.
Hours carrying very little traffic are excluded before any road is called busy, so an empty carriageway during overnight roadworks cannot appear here as congestion. The full method is on the how these figures are measured page.
Questions about this ranking
Which road in England slows down the most?
Of the 35 roads measured here by at least 5 sensors, the M18 drops furthest below its own normal speed. Its worst hour is Friday at 15:00, averaging 44 mph, about 36% below the speed that road runs at when it is clear. That is measured from National Highways roadside sensors between 1 May 2026 and 15 June 2026, not estimated. It means the road falls furthest relative to itself, which is not the same as being the slowest road in miles per hour. Roads carried by fewer than 5 sensors are listed on the page but are not used for this answer, because a handful of sensors cannot describe a whole road.
Which road is least affected by rush hour?
The M49 varies least. Even at its worst hour, Friday at 12:00, it averages 63 mph, only about 6% below its normal speed. A road can appear here either because it is genuinely free flowing or because it is slow all day and therefore has little room left to fall.
Does a bigger drop mean a slower road?
No, and this is the most common way to misread a ranking like this one. Every figure is measured against that road's own free-flowing speed, because sensors on bends and slip roads never reach 70 mph and comparing them with the limit would invent congestion. So a road with a 40% drop is falling further from its own normal than a road with a 20% drop, but it may still be moving faster in miles per hour. Both numbers are given in the table for that reason.