Highway Code rule 126: Stopping Distances and Safe Following Gaps
Highway Code rule 126 says: “You should • leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops.”
The official rule
Stopping distances. Drive at a speed that will allow you to stop well within the distance you can see to be clear. You should • leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops. The safe rule is never to get closer than the overall stopping distance (see Typical Stopping Distances diagram) • allow at least a two-second gap between you and the vehicle in front on high-speed roads and in tunnels where visibility is reduced. The gap should be at least doubled on wet roads and up to ten times greater on icy roads • remember, large vehicles and motorcycles need a greater distance to stop. If driving a large vehicle in a tunnel, you should allow a four-second gap between you and the vehicle in front If you have to stop in a tunnel, leave at least a 5-metre gap between you and the vehicle in front. Typical stopping distances (thinking distance + braking distance = overall stopping distance): • 20 mph (32 km/h): 6 m + 6 m = 12 metres (40 feet), or three car lengths • 30 mph (48 km/h): 9 m + 14 m = 23 metres (75 feet), or six car lengths • 40 mph (64 km/h): 12 m + 24 m = 36 metres (118 feet), or nine car lengths • 50 mph (80 km/h): 15 m + 38 m = 53 metres (175 feet), or thirteen car lengths • 60 mph (96 km/h): 18 m + 55 m = 73 metres (240 feet), or eighteen car lengths • 70 mph (112 km/h): 21 m + 75 m = 96 metres (315 feet), or twenty-four car lengths The distances shown are a general guide. The distance will depend on your attention (thinking distance), the road surface, the weather conditions and the condition of your vehicle at the time. Average car length = 4 metres (13 feet). Tailgating is where the gap between you and the vehicle in front is too small for you to be able to stop safely if the vehicle in front suddenly brakes. Tailgating is dangerous, intimidating and can cause collisions, especially when driving at speed. Keeping a safe distance from the vehicle in front gives you time to react and stop if necessary. Dangerous and careless driving offences, such as tailgating, are enforced by the police.
In plain English
Your stopping distance is your thinking distance plus your braking distance, and it grows quickly with speed. For example, at 30 mph a car needs about 23 metres to stop, but at 70 mph it needs 96 metres. On the motorway, pick a fixed point like a bridge: if you pass it less than two seconds after the car in front, drop back, and double the gap when the road is wet.
Questions about rule 126
- What does Highway Code rule 126 say?
- Rule 126 says: “You should • leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops.”
- Is Highway Code rule 126 a legal requirement?
- The Highway Code marks legal requirements with MUST or MUST NOT and cites the law behind them. Its other rules are advice: not following them will not on its own lead to prosecution, but can be used in evidence in court. Read rule 126 in full on gov.uk to see which parts are legal requirements.
- Which part of the Highway Code is rule 126 in?
- Rule 126 is in the "General rules, techniques and advice for all drivers and riders" section, which covers rules 103 to 158 on gov.uk.
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