What does Highway Code Rule 91 say?

Rule 91 (Fitness to drive (rules 90 to 94)) Driving when you are tired greatly increases your risk of collision. 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 91 the law or just guidance?

Rule 91 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 91 tested on the driving test?

Examiners specifically assess how you respond to vulnerable road users, pedestrians at crossings, cyclists, horse riders and motorcyclists. Late or missing observations here are a common cause of a serious fault, so anticipation is marked closely throughout the drive.

What are the common mistakes related to Rule 91?

The faults examiners most often record around this part of the Code are: passing cyclists or horses too closely or too fast; failing to anticipate a pedestrian stepping out near a crossing or parked cars; not giving way at a crossing when someone is clearly waiting. Rehearsing the safe habit during lessons is the most reliable way to avoid them.

Highway Code · Rule 91

Highway Code Rule 91

Rules for drivers and motorcyclists (89 to 102). Advisory guidance you are expected to follow.

Rules for drivers and motorcyclists
Advisory rule
OGL v3.0

What the rule says

Advisory

Rule 91 (Fitness to drive (rules 90 to 94)) Driving when you are tired greatly increases your risk of collision. To minimise this risk

make sure you are fit to drive. Do not begin a journey if you are tired. Get sufficient sleep before embarking on a long journey
avoid undertaking long journeys between midnight and 6 am, when natural alertness is at a minimum
plan your journey to take sufficient breaks. A minimum break of at least 15 minutes after every two hours of driving is recommended
if you feel sleepy, stop in a safe place. Do not stop in an emergency area or on a hard shoulder of a motorway (see Rule 262 for guidance on places to take a break when travelling on motorways).

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 91 comes down to one idea: rule 91 (Fitness to drive (rules 90 to 94)) Driving when you are tired greatly increases your risk of collision. 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 rules for drivers and motorcyclists 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 rules for drivers and motorcyclists 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 91 matters on the road

Pedestrians, cyclists, motorcyclists and horse riders have little protection in a collision, so a moment of inattention from a driver can cause serious harm. Anticipating and giving them room is one of the clearest signs of a safe, considerate driver.

Common faults examiners record

In the rules for drivers and motorcyclists 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:

Passing cyclists or horses too closely or too fast.
Failing to anticipate a pedestrian stepping out near a crossing or parked cars.
Not giving way at a crossing when someone is clearly waiting.

On the day

Imagine approaching a cyclist on a narrow stretch during the drive. Applying Rule 91 means easing off early, holding back until you can see it is genuinely safe, then passing wide and slow before returning to your line. The examiner is watching for exactly that anticipation, not a squeeze past at speed.

Quick checklist

Scan ahead for pedestrians, cyclists and riders well before you reach them.
Give them room and time, pass wide and slow.
Be ready to stop at crossings and side roads.

More from Rules for drivers and motorcyclists

Related Highway Code rules

Rule 91, your questions

: Rule 91 (Fitness to drive (rules 90 to 94)) Driving when you are tired greatly increases your risk of collision. 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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