The government's Be Ready guidance gives a specific car kit for winter: a torch, phone charger, warm clothes, blankets, high-visibility clothing, jump leads, food and drink, a shovel and a first aid kit. Most of it is cheap, all of it fits in one box, and it stays in the boot from October to April.
The kit
Before a winter journey
Check the warnings
Met Office weather warnings and National Highways or Traffic Scotland for road closures. An amber warning for snow is a reason not to travel unless you must.
Fuel above a quarter, EV above 40 per cent
Fuel is heat and charge. Electric range falls sharply in cold weather, and a queue on a closed motorway is where it runs out.
Tell someone your route and expected arrival
So that if you stop answering, someone knows where to look.
Clear the whole car
All windows, lights, mirrors and the roof. Snow sliding off the roof onto your windscreen at 50 mph is a known cause of crashes, and driving with obscured windows is an offence.
If you are stranded
Unless you can see a safe building within a short walk, stay in the vehicle. It is shelter, it is visible to rescuers, and people who set off on foot in snow get lost. The exception is a motorway: if you can safely leave the car on the hard shoulder, get behind the barrier and well away from traffic.
- Put on all your layers before you feel cold. Blanket over the legs.
- Run the engine for about ten minutes an hour to warm up and charge phones. Check the exhaust is clear of snow first and crack a window.
- Turn on hazard lights. At night, keep the interior light on when the engine runs.
- Call 999 if anyone is in danger; otherwise your breakdown provider, and tell family where you are.
- Eat and drink regularly. Sip water; a thermos of something hot if you planned ahead.
- Move your arms and legs every so often and do not fall asleep with the engine running.
Floodwater and cars
Do not drive into floodwater, however shallow it looks. Around 15 cm stalls most cars and 30 cm of moving water floats one. The road beneath may have washed away and manhole covers lift. If your car does stall in water, do not restart it; get out, move to higher ground and call for help. If water is rising around a car, get out through the window early rather than wait for the door to be forced by the pressure. The flood guide has more.
Summer
Swap the shovel and grit for extra water, sunscreen, sunshades and a small battery fan. Never leave children or pets in a parked car in warm weather, even briefly: the inside temperature can rise 10°C in ten minutes. See the heatwave guide.
Jump starters, folding shovels and hi-vis vests are on the recommended kit page. None of the links on this site currently earn us a commission; if that changes we will say so.
Common questions
Is a car emergency kit a legal requirement in the UK?
No, unlike some European countries where a high-visibility vest and warning triangle are mandatory. But if you drive to France, Spain or Italy you must carry them, so it costs nothing to keep them in the boot year-round.
Should I keep the engine running to stay warm if stranded?
Run the engine for about ten minutes each hour to warm the car and charge your phone, but first check the exhaust is clear of snow, and keep a window slightly open. A blocked exhaust fills the cabin with carbon monoxide. Never sleep with the engine running.
How much fuel should I keep in the tank in winter?
Never let it drop below a quarter in winter. Fuel is heat, charge and the ability to move when the road reopens. Electric vehicles should be kept above 30 to 40 per cent in cold weather, as range falls significantly.
Can I drive through floodwater?
No. Thirty centimetres of moving water can float a car, and 15 cm can stall most engines. You cannot see the depth, the road surface or whether the drain cover has lifted. Turn around; the long way round is quicker than a written-off car.