How Busy Is the M42?
This page answers one question: how much traffic does each stretch of the M42 carry? The figures are annual average daily flows from the Department for Transport road traffic statistics, 2025, both directions together, listed in junction order from the M5 to the A42.
The M42 junction by junction
| Stretch | Vehicles per day | Lorries | Length counted |
|---|---|---|---|
| M5 J4A to J1 | 98,893 | 11,296 | 0.6 miles |
| J1 to J2 | 115,815 | 11,711 | 4.2 miles |
| J2 to J3 | 114,179 | 11,224 | 2.7 miles |
| J3 to J3A | 126,742 | 12,185 | 3.4 miles |
| J3A to J4 | 129,185 | 14,559 | 0.7 miles |
| J4 to J5 | 136,724 | 14,082 | 2.4 miles |
| J5 to J6 | 109,996 | 11,483 | 3.6 miles |
| J6 to J7 | 128,313 | 13,382 | 2.1 miles |
| J7 to J7A | 99,354 | 10,902 | 0.4 miles |
| J8 to J9 | 104,732 | 16,242 | 1.6 miles |
| J9 to J10 | 79,468 | 11,558 | 5.9 miles |
| J10 to J11 | 67,744 | 10,831 | 5.8 miles |
| J11 onto the A42 | 47,583 | 6,624 | 0.4 miles |
Duplicates removed. Two stretches are counted at two points, split where the road crosses a local authority boundary. We show the busier point for each: J3A to J4 (the other point recorded 125,023) and J10 to J11 (the other recorded 66,124). The J3A to J4 figure we show is a DfT estimate; the other point was counted. Short links and slip roads are left out of this table and described on the junction pages.
The DfT labels some stretches in its own words: M5 J4A to J1 is "M42 split to Jn1", J3 to J3A is "3 to M42", J7 to J7A is "LA boundary to 7a", and J8 to J9 is counted from the M6 Toll interchange north of Gilson to Junction 9. The length column is the section the count point represents, not the full distance between junctions.
The busiest part of the M42
The busiest stretch is Junction 4 to Junction 5, between Shirley (A34) and Solihull (A41), at 136,724 vehicles a day. The four stretches from Junction 3 to Junction 5 and from Junction 6 to Junction 7 all carry more than 125,000. This is the part of the road between the M40 and the M6, and it is where the Active Traffic Management pilot began in 2006.
Junction 5 to Junction 6 is quieter than the stretches either side, at 109,996, before the count rises again beyond Junction 6, the junction for the airport, the NEC and the A45.
The quietest part
North of the M6 Toll links, traffic falls away. Junction 9 to Junction 10 carries 79,468 and Junction 10 to Junction 11 carries 67,744 — about half the busiest stretch. The last counted point, where the motorway hands over to the A42, carries 47,583.
How the M42 compares
For comparisons with the roads it meets, see the statistics on M40 Traffic, M6 Traffic and M5 Traffic. One-direction figures are on the northbound and southbound pages.
Traffic count figures on this page are from the Department for Transport road traffic statistics, 2025.