About M3 Traffic
M3 Traffic is a free, independent website dedicated to the M3 motorway — bringing together the latest M3 traffic news, reports, roadworks and delays in one clear, easy-to-use place. It’s part of our Traffic News England network, a family of road-specific sites that help drivers check their route before they set off.
Helping M3 drivers
The M3 runs 58.6 miles (94.3 km) from Junction 1 at Sunbury in south-west London to Junction 14, where it ends at the M27 outside Southampton. It is the main road between London and the central south coast, and it carries between 56,135 and 140,750 vehicles a day depending where you join it — two and a half times more at the Southampton end than across the middle of Hampshire. Commuter traffic into Surrey and Basingstoke, holiday traffic to the coast and freight from Southampton Docks all share it, so roadworks, delays and incidents are common. It always pays to check the latest M3 traffic news before you set off.
Other motorways
The M3 meets the M25 at Junction 2 and ends at the M27 at Junction 14. Its two biggest trunk-road connections are the A303 at Junction 8, for Salisbury and the West Country, and the A34 at Junction 9, for Newbury, Oxford and the Midlands. If your journey also uses one of them, our sister sites cover them in the same easy format: M1 Traffic, M60 Traffic, M25 Traffic, M4 Traffic and M6 Traffic.
Find the latest M3 traffic reports
You can find all the latest M3 traffic reports quickly and easily on our Latest M3 Traffic News page — with dedicated Roadworks and Accidents pages too.
Who Publishes M3 Traffic
M3 Traffic is published by Corporate Ace Limited, a company registered in England and Wales.
- Company number: 04435502
- Registered office: 24 St. Marys Way, Burghfield Common, Reading, England, RG7 3YR
- VAT number: GB863826885
- Registered with the Information Commissioner’s Office: Z1734656
- Email:
Where Our Data Comes From
Live traffic information on this site is powered by National Highways’ Transport Data Feeds. Traffic counts come from the Department for Transport’s road traffic statistics for 2025, published 20 May 2026. How we present and explain those figures is our own work.
Contains public sector information licensed under the Open Government Licence v3.0.