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Highway Code · Rule 231

Highway Code Rule 231

Driving in adverse weather conditions (226 to 237). Advisory guidance you are expected to follow.

  • Driving in adverse weather conditions
  • Advisory rule
  • OGL v3.0

What the rule says

Advisory

Rule 231 (Icy and snowy weather (rules 228 to 231)) Drive extremely carefully when the roads are icy. Avoid sudden actions as these could cause loss of control. You should

  • drive at a slow speed in as high a gear as possible; accelerate and brake very gently
  • drive particularly slowly on bends where loss of control is more likely. Brake progressively on the straight before you reach a bend. Having slowed down, steer smoothly round the bend, avoiding sudden actions
  • check your grip on the road surface when there is snow or ice by choosing a safe place to brake gently. If the steering feels unresponsive this may indicate ice and your vehicle losing its grip on the road. When travelling on ice, tyres make virtually no noise.

Rule text reproduced verbatim from the official Highway Code (Crown copyright) under the Open Government Licence v3.0, see the attribution at the foot of this page.

In plain English

Stripped of the formal wording, Rule 231 comes down to one idea: rule 231 (Icy and snowy weather (rules 228 to 231)) Drive extremely carefully when the roads are icy. It is advice rather than law, but examiners and the courts still treat it as the expected standard of safe driving.

It belongs to the driving in adverse weather conditions part of the Code, the habits a confident, considerate driver builds until they are automatic. The aim is not to memorise the sentence word for word, but to understand the hazard it protects you from, so you apply it without having to think when it counts.

If you are learning, treat this rule as one piece of a connected set rather than an isolated fact. The related rules below sit in the same section and reinforce each other, reading them together is how the driving in adverse weather conditions part of the Code starts to feel like common sense rather than a list to revise.

Because this is advisory rather than legal, no one will fine you for the rule alone, but ignoring it can still count against you in a careless-driving case, and it will cost you faults on the test. Either way, the safe move is to build the habit early, while a driving instructor can correct it, rather than relearning it under test pressure. That is exactly what the practice routes and coaching in the DriveRoutes app are designed to help with, turning the rules below into the way you naturally drive.

Why rule 231 matters on the road

Rain, fog, ice and low sun change how your car behaves and how far you can see. Adjusting early, before you actually need the extra space, is what keeps a tricky drive uneventful rather than dangerous.

Common faults examiners record

In the driving in adverse weather conditions part of the Code, the faults most often written on the marking sheet tend to be the same handful. Knowing them in advance is the quickest way to drive them out of your own habits:

  • Carrying too much speed for the visibility or grip.
  • Forgetting to use, or switch off, lights as conditions change.
  • Following too closely when stopping distances have grown.

On the day

Picture the road surface darkening with rain mid-test. Applying Rule 231 means easing your speed, lengthening your following distance and using lights appropriately, adjusting before the conditions force your hand rather than after.

Quick checklist

  • Match your speed to what you can actually see and feel.
  • Use the right lights for the conditions.
  • Leave a bigger gap whenever grip or visibility drops.

More from Driving in adverse weather conditions

Related Highway Code rules

Rule 231, your questions

Rule 231 (Icy and snowy weather (rules 228 to 231)) Drive extremely carefully when the roads are icy. It is advisory guidance rather than law, but you are still expected to follow it and an examiner can mark a fault if you do not.

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