Winter tires vs all-season tires: which do you need?

The short version: if your winters bring regular snow, ice or long spells of near-freezing weather, a set of four winter tires is the safest choice. If snow is rare, all-season tires are fine. If you get some snow but don't want to swap tires twice a year, look at all-weather tires carrying the three-peak mountain snowflake symbol.

When to stop driving

Whatever tires you have, don't set off in snow or ice on tires that are worn close to the legal limit, damaged, or badly under-inflated. Grip on snow falls off fast as tread wears. If you start to slide, can't stop where you expect to, or the tire pressure light comes on in bad weather, slow down, pull over somewhere safe and check before you go on.

The three types, side by side

A note on names. In the US and Canada, "all-season" usually means a three-season tire with M+S on the sidewall, and "all-weather" means one that also passed the snow test. In the UK and Europe, "all-season tyres" (or "tyres", as UK readers search it) are often closer to as North American all-weather tires, and many carry the snowflake symbol. Check the sidewall, not the name.

Why cold matters, not just snow

Winter tires are designed for temperatures below about 7°C (45°F), according to the RAC. Below that, the rubber in summer and all-season tires stiffens and grips less, while winter rubber stays soft. Winter tires also have deeper grooves and many sipes, which bite into snow and clear slush.

This is why winter tires help on cold, dry or wet roads too, not only in snow. In TyreSafe testing reported by the RAC:

So in warm weather winter tires stop slightly longer, but in cold weather they stop shorter. The RAC says the gap widens considerably on snow.

M+S vs the snowflake symbol

• M+S (mud and snow), also written M/S or MS: describes a tread pattern meant to work better in snow than a normal tire. Continental points out that this performance is neither defined nor measured. Many North American all-season and SUV tires carry it.
• Three-peak mountain snowflake (3PMSF, or "Alpine" symbol): the tire passed a standard traction test (ASTM F1805) on medium-packed snow. This is the mark that winter-tire laws in Quebec and Germany look for.

The snowflake test measures traction on packed snow, not grip on ice, which is one reason dedicated winter tires still beat all-weather tires on ice even though both carry the same symbol.

What the tests show

Consumer Reports tests winter tires for snow traction on snow and ice braking on a skating rink, and weights those most heavily in its winter tire scores. Its conclusions:

• Winter tires give the best grip on snow and ice. The trade-off is shorter tread life and, for most models, less grip than all-season tires on dry and wet roads.
• All-weather tires come close to winter tires in winter traction and can stay on all year.
• All-season tires are the baseline for dry and wet roads, with less winter grip.

The difference only lasts while there is tread. Consumer Reports recommends replacing tires at 4/32 inch (about 3 mm) because snow grip drops significantly below that. Continental recommends at least 4 mm of tread on winter tires used in winter conditions. Both are well above the legal minimum; see how long tires last for the legal limits and how to measure.

Which should you buy?

Snowy winters (much of Canada, the northern US, Scandinavia, the Alps, high ground anywhere). Fit four winter tires for the cold months. All-wheel drive helps you pull away but does not help you stop or steer: that comes from the tires.

Some snow, mostly cold and wet (the US Mid-Atlantic and Pacific Northwest, much of Germany, northern England and Scotland). All-weather tires with the snowflake symbol are a sensible single set. Choose winter tires if you live up a hill, in the countryside, or must drive whatever the weather.

Mild winters (the US South and West Coast, most of southern England, most of Australia). All-season tires, or the summer tires your car came with, are fine. Slow down on the few icy days, or stay home.

Australia. Winter tires are rarely needed outside the alpine areas. If you drive to Victoria's alpine resorts (such as Mt Buller, Falls Creek or Mt Hotham) in the declared snow season, you must carry snow chains and fit them when told to. Check the rules for your resort before you go.

Where winter tires are the law

Rules change, so check the official source before you travel.

• Germany: there is no fixed date. Under the situational rule in the road traffic regulations (StVO § 2), you may only drive in black ice, snow, slush or frost if all wheels have winter-rated tires. Since 1 October 2024, only tires with the snowflake symbol count; older M+S-only tires were accepted until 30 September 2024. The basic fine is €60 and one penalty point, rising if you hold up or endanger others or cause a crash.
• Quebec: winter tires are mandatory from December 1 to March 15 inclusive on passenger vehicles registered in Quebec, including rentals. Only tires with the snowflake symbol, or studded tires, count.
• British Columbia: winter tires are required on some highways from October 1 to April 30. Watch for the signs.
• The rest of Canada: not required, but some insurers offer a discount for winter tires.
• The UK: winter tires are not required. In the US there is no nationwide requirement; follow any local signs about chains or traction tires on mountain roads.

Other European countries have their own winter tire or snow chain rules. Check them before driving there in winter, especially in a rental car or your own car from the UK.

Fit all four, not two

Consumer Reports says to always use winter tires in sets of four, whatever drives the wheels. With winter tires only on the front, the rear tires lose grip first in a corner or under braking and the back of the car can swing round. With them only on the rear, the front can push wide and fail to steer. Matching all four keeps the car predictable.

What it costs

Prices depend on your tire size, so there is no single figure. The RAC says winter tires cost on average a little more than an equivalent summer tire. The real costs are:

• Two sets instead of one. A set of four winter tires is a big outlay, especially if you add a second set of wheels. But while the winter set is on, your other tires aren't wearing, so both sets last longer.
• Swapping twice a year. Having winter tires already mounted on their own wheels makes each swap quicker and cheaper, and saves wear on the tires from repeated fitting.
• Storage. If you have no garage or shed, many tire centres offer storage (a "tyre hotel" in the UK) for a fee per season. Store tires clean, dry, out of sunlight and away from heaters.
• All-weather tires avoid most of this: one set, no swaps, no storage, at the cost of some winter grip and some summer sharpness.

When to swap

• On: when temperatures settle around 7°C (45°F) or below, before the first snow. Consumer Reports suggests buying before the first frost, because popular sizes sell out once snow arrives. In Quebec, have them on by December 1.
• Off: when spring temperatures stay above about 7°C. Quebec's rule ends March 15, but you can keep them on longer if your area still gets late snow.
• At every swap: check tread depth and age, set the tire pressure to the figure on the door pillar or in your owner's manual, and note which tire came off which corner so you can rotate them next time.
• Through the winter: tire pressure drops as the air gets colder, so check monthly. A portable tire inflator makes this easy at home.

Getting ready for winter? See also what to do when your car won't start in the cold and how to defrost a windshield fast.