What does Highway Code Rule 251 say?

Rule 251 (Parking at night (rules 248 to 252)) Parking in fog. 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.

Is Rule 251 the law or just guidance?

Rule 251 is advisory, it does not use “MUST” or “MUST NOT”, so it is not directly enforceable as a standalone offence. You are still expected to follow it, and ignoring it can contribute to a careless- or dangerous-driving charge and to faults on your test.

How is Rule 251 tested on the driving test?

Parking and waiting rules underpin the controlled stop and the manoeuvre exercises (parallel park, bay park, pull up on the right). The examiner checks that you stop legally and safely, with the right observations, before and after the manoeuvre.

What are the common mistakes related to Rule 251?

The faults examiners most often record around this part of the Code are: insufficient observation during the reversing manoeuvre; finishing the manoeuvre poorly positioned or too far from the kerb; moving off afterwards without a proper all-round check. Rehearsing the safe habit during lessons is the most reliable way to avoid them.

Highway Code · Rule 251

Highway Code Rule 251

Waiting and parking (238 to 252). Advisory guidance you are expected to follow.

Waiting and parking
Advisory rule
OGL v3.0

What the rule says

Advisory

Rule 251 (Parking at night (rules 248 to 252)) Parking in fog. It is especially dangerous to park on the road in fog. If it is unavoidable, leave your parking lights or sidelights on.

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 251 comes down to one idea: rule 251 (Parking at night (rules 248 to 252)) Parking in fog. 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 waiting and parking 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 waiting and parking 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 251 matters on the road

Stopping and parking badly creates hazards for everyone, blocking sightlines, forcing others into the path of oncoming traffic, or trapping pedestrians. Doing it cleanly keeps the road flowing and prevents the close calls that careless parking causes.

Common faults examiners record

In the waiting and parking 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:

Insufficient observation during the reversing manoeuvre.
Finishing the manoeuvre poorly positioned or too far from the kerb.
Moving off afterwards without a proper all-round check.

On the day

Picture the examiner asking for a manoeuvre. Applying Rule 251 means choosing a safe, legal spot, taking all-round observation before and during the exercise, and finishing tidily positioned. The manoeuvre itself matters less than the observation and control you show around it.

Quick checklist

Pick a safe, legal place to stop or manoeuvre.
Take all-round observation before and during the exercise.
Check fully again before you move off.

Related Highway Code rules

Rule 251, your questions

: Rule 251 (Parking at night (rules 248 to 252)) Parking in fog. 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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