Snow chains and snow socks are traction aids for snow and ice, not year-round equipment, and the law treats them that way. The single rule that applies almost everywhere is that they may be used only on roads covered with snow or ice.
The snow-or-ice-only rule
On bare tarmac, chains chew up the road surface and damage the tyre, and socks wear through in minutes. So both are permitted only where there is a continuous covering of snow or ice, and must be removed once the road is clear. Fitting them for a dusting that has already melted, or leaving them on after the snow ends, is both pointless and, in many places, an offence.
Where conditions or signs demand them, chains go on the driven wheels, at least the two that put the power down. After fitting, the advice is to drive a short distance and re-tension, since chains bed in and slacken slightly under load.
Low speeds only
Chains and socks change how a car behaves and are built for low speeds. A limit of around 50km/h (about 30mph) is common, and sometimes lower. They are meant for getting safely across a snow-covered section, a mountain pass, an unploughed approach road, not for covering distance. Pushing the speed risks throwing a chain and damaging the car.
Chains versus socks in law
The two are not always treated the same:
- Snow chains are the traditional steel-link devices and are accepted everywhere chains are required
- Snow socks are textile covers, made to the EN 16662-1 standard, lighter and far easier to fit
Socks are accepted as a chain-equivalent in some countries, such as Austria and Germany. But on roads where chains are specifically mandated, including parts of France and Italy, often marked with a blue chains-required sign, socks may not be accepted as a substitute. Anyone relying on socks for a trip should check that they count where they are going.
In the UK and abroad
In Britain, chains and socks are legal to use but rarely needed, and the same snow-or-ice-only principle applies. The place they matter most for UK drivers is abroad, where some mountain roads require chains to be carried, and sometimes fitted, even on a car already wearing winter tyres. They are best thought of as a back-up to good tyres rather than a replacement, and for regular cold-weather driving a snowflake-rated set matters more than the chains themselves, and the snowflake options are easy to compare by size at Tyres.co.uk and other tyre sites.
From the workshop: the mistake we hear about is socks bought for a French ski trip that turned out not to count where chains were the rule. Practise fitting whatever you carry, on the driveway, in the dry, before you ever need it in a blizzard.
Sources and accuracy. The use rules, the sock standard and the country differences here reflect guidance at the time of writing, which can change, and country specifics should be confirmed before travel. If anything here looks wrong, get in touch and we will check it and put it right.
Common questions
When can snow chains be used?+
Only on roads covered with snow or ice. On bare tarmac, chains damage both the road surface and the tyre, so they must be fitted only where there is a continuous layer of snow or ice, and removed as soon as the road is clear.
Are snow socks as good as chains in law?+
Not everywhere. Textile snow socks made to the EN 16662-1 standard are accepted as a chain-equivalent in some countries, such as Austria and Germany. But on roads where chains are specifically mandated, including parts of France and Italy, socks may not be accepted as a substitute.
How fast can you drive with chains or socks fitted?+
Slowly. Chains and socks are designed for low speeds, commonly a limit of around 50km/h (about 30mph), and sometimes lower. They are a short-distance traction aid for snow-covered sections, not something to drive on at normal speeds.
Which wheels do snow chains go on?+
The driven wheels, the ones that put the power down. Fitting to at least the two drive wheels is the rule. After fitting, it is worth driving a short distance and re-tensioning, as chains bed in and loosen slightly once they take load.