The road runs west from junction 10A of the M6 motorway near Essington, Staffordshire (Map). It passes south of Featherstone near junction 1 and then north of Bushbury before reaching junction 2. Just before junction 3 with Albrighton the road enters Shropshire. It then passes to the north of Shifnal. Between junction 4 and junction 5, the road passes across the Wolverhampton to Shrewsbury railway line, and through the centre of Telford. Between junctions 6 and 7, the road runs around the south of Wellington before joining the A5 (Map), which continues on to Shrewsbury as dual carriageway.