TfL JamCams Explained
What are they, how do they work, and how can you use them to check London traffic before you drive?
JamCams are Transport for London's network of roadside traffic monitoring cameras positioned at key junctions, busy roads and pinch points across Greater London. The name "JamCam" comes from their primary purpose: helping identify and monitor traffic jams across the network.
The cameras capture still images (typically refreshed every few minutes) or short video clips showing current road conditions. These images are made available as open data by TfL under their developer API, which is how third-party sites like JamCams.co.uk can show you the live feeds.
JamCams are not speed cameras, ANPR enforcement cameras or CCTV for police use. They are purely traffic monitoring tools.
Each JamCam is a weatherproof camera mounted on a pole or gantry at a road junction or busy stretch of road. The cameras are connected to TfL's Urban Traffic Control (UTC) system — London's centralised traffic management network which also controls thousands of traffic signals across the city.
TfL's traffic engineers at their 24/7 operations centre in Southwark can view any camera in real time to assess incidents and adjust signal timings to manage flow. Separately, the camera images are pushed to TfL's open data API, where they become publicly accessible.
The images update on a regular schedule — typically every 5 to 10 minutes — rather than being true live video. This is why you may sometimes notice the timestamp on an image is a few minutes old. During incidents, operators may increase the refresh frequency for affected cameras.
JamCams are used exclusively for traffic monitoring and management. They do not record number plates, measure vehicle speeds, or feed into enforcement systems. The images are low-resolution overviews of traffic conditions — not individual vehicle detail.
There are over 900 JamCams distributed across Greater London, with the highest concentration in central London and at key route pinch points. You'll find them at:
The coverage is significantly better in inner London than outer London. Some outer boroughs have relatively few cameras. You can browse the full map of camera locations on our interactive map.
JamCams are most useful when used before you travel — check the cameras along your planned route to see if there are any obvious queues, incidents or roadworks before you commit to a road.