How long do winter tires last?

You'll often see “four to six seasons” quoted, and for an average Toronto driver that's a fair rough guide. But a winter tire doesn't wear out by counting winters. It wears out two ways: the tread gets too shallow, or the rubber gets too old. Whichever comes first is when the set is done.

Tread: replace at 4/32"

A new winter tire starts with deep tread, often around 10/32 to 12/32 of an inch. The deep grooves and small cuts across the blocks are what pack with snow, push slush out of the way and bite on ice. As the tire wears, those grooves get shallow and that ability goes with them.

Once a winter tire is down to about 4/32 of an inch, roughly half worn, it's finished as a winter tire. It's still legal on the road, since the legal floor is much lower, but in snow it will behave more like a worn all-season. Many winter tires have a second set of wear bars in the grooves that show you when you've reached that point. If you're not sure, we'll measure it when the set comes in for the changeover.

Age: the date on the sidewall

Rubber hardens as it ages, whether the car moves or not. A ten-year-old winter tire with plenty of tread can still be too hard to grip on a cold road, and from the outside it looks fine.

To check yours, find the code starting with DOT on the sidewall. The last four digits are the week and year the tire was made: 2421 means week 24 of 2021. Many tire makers recommend having tires inspected every year once they're about five years old, and replacing any tire ten years after it was made, however much tread is left. Look for small cracks in the sidewall or between the tread blocks too. That's age showing.

What wears winter tires out faster

Leaving them on into summer. The soft compound that grips in January wears fast on hot pavement. A set left on through the summer can lose more tread in a few months than in a couple of winters. When daytime highs stay above about 7°C, swap back.

Low pressure. Tires lose pressure as the temperature drops, so a set that was right in October can be well down by January. Underinflated tires wear on the edges and run hotter. Check them monthly in winter.

How they spend the summer.Sun, heat and a damp garage floor all age rubber. Stored clean, dry, out of the light and away from heat, a set lasts noticeably longer. If you'd rather not keep them yourself, see tire storage.

Never rotating them. On a front-wheel-drive car the front pair wears faster. Swapping positions each season evens it out, which is why we tag stored tires by position.

Buying used winter tires

Everything above is also how to judge a used set. Check the date code first, then the tread depth, then the sidewalls for cuts, bulges and cracking. A used set with a recent date and good tread is a very sensible way to save money; a cheap set that's eight years old is not a bargain at any price. We check every used tire we sell for tread, age and sidewall damage; see used tires.

Thinking of replacing just two? Read do you need 4 winter tires first.