The M3 runs 58.6 miles from Junction 1 at Sunbury to Junction 14 at the M27, through 14 numbered junctions (15 counting J4A) and 15 measured stretches of mainline. These pages help you find the part of it you actually drive.

Maps of the M3

• Map of the M3 motorway junctions

The busiest junctions on the M3

Each of these pages carries the official traffic counts for that stretch alongside the traffic news affecting it:

• M3 Junctions 12 to 14 (Eastleigh, Chilworth & the M27) — 140,750 vehicles a day, the busiest stretch of the M3
• M3 Junction 10 (Chilcomb, Winchester) — 126,217 a day and more lorries than anywhere else on the M3
• M3 Junction 3 (Lightwater & Bagshot) — 123,417 a day, the busiest counted stretch in Surrey
• M3 Junctions 4 and 4A (Frimley, Farnborough & Fleet) — 118,589 a day, and the most one-sided stretch of the motorway
• M3 Junction 2 (the M25 interchange) — 113,905 a day, where about 45% of the traffic changes motorway
• M3 Junction 9 (A34 & Winchester) — 110,741 a day, where the traffic almost doubles

For the whole motorway, see how busy the M3 is junction by junction.