Between 1 October and 30 April, designated highways in British Columbia require winter tires. The routes are signed, and they cover most mountain passes and interior highways — the Coquihalla, the Sea to Sky, the Okanagan Connector among them. Surrey’s own roads carry no such requirement, which is why the question comes up here every autumn: the rule attaches to the road you drive on, not to the city you live in. Anyone leaving the Lower Mainland between those dates is subject to it.
What counts as a winter tire
Two markings satisfy the regulation, and they are not equal.
- The three-peak mountain snowflake
Awarded on tested performance in severe snow. The compound is formulated to stay pliable in the cold, which is where most of the grip actually comes from.
- M+S (mud and snow)
Legal on designated routes with at least 3.5 mm of tread. It describes a tread pattern rather than a tested result, and on ice and packed snow the difference from a snowflake-rated tire is substantial.
Either way the tread depth matters: 3.5 mm is the legal minimum on designated highways, against 1.6 mm for tires in general. A winter tire below roughly 4 mm has lost most of what made it one.
Why the compound matters more than the tread pattern
The number worth remembering is 7°C. Below it, the rubber in a summer tire hardens and stops keying into the road surface — on dry pavement as much as on snow. That is why a winter tire is worth fitting across the Lower Mainland even where no sign demands it and snow rarely settles: most of the benefit is collected on cold, wet mornings, which we have a great many more of than we have snow days.
It also explains why leaving winter tires on through the summer is a poor trade. Above that same temperature the soft compound wears quickly, so a set kept on year-round can lose a season of life in a few warm months while giving up dry-road braking in exchange.
When to book
September, before the deadline and before the queue. Demand across every shop in the Lower Mainland spikes in the week after the first cold snap, and the changeover is a quick job that becomes a wait simply because everyone arrives at once. If you run a second set of wheels the swap is quicker still, since the tires do not have to come off the rims.
It is also the moment to have the wear pattern read across all four. Feathering, one-shoulder wear and cupping each point at a specific alignment or suspension fault, and catching one at the changeover is how it gets corrected before it costs a set of tires.
Winter tire questions
Are winter tires mandatory in BC?
On designated highways, yes. From 1 October to 30 April signed routes require winter tires, and that includes most mountain passes and interior highways. On municipal roads in Surrey and the rest of the Lower Mainland there is no legal requirement — but the rule follows the road, not where you live, so a driver from Surrey heading to the interior is subject to it the moment they reach the signs.
What date do I need winter tires by in BC?
1 October for most designated routes. Some highways — chiefly a number of mountain passes — extend the requirement to 31 March or 30 April rather than ending it in March, so the sign at the start of the route is the authority rather than a single remembered date.
Does the M+S symbol count as a winter tire?
For legal purposes on BC's designated highways, yes, provided the tread is at least 3.5 mm deep. In terms of actual performance it is the weaker of the two: M+S describes a tread pattern, while the three-peak mountain snowflake is awarded on tested performance in severe snow and comes with a compound formulated to stay soft in the cold.
How much tread do winter tires need in BC?
At least 3.5 mm to be legal on designated routes, which is more than the 1.6 mm minimum that applies to tires generally. A winter tire much below about 4 mm has lost most of what makes it a winter tire, so the legal floor and the useful floor are close together here.
Do I need winter tires if I have all-wheel drive?
All-wheel drive helps you accelerate. It does nothing for braking or cornering, both of which depend entirely on the four contact patches. An all-wheel-drive vehicle on summer tires stops no better on ice than a front-wheel-drive one — it simply reaches the corner faster. The legal requirement on designated routes applies regardless of drivetrain.
When should I book the changeover?
September is the sensible month — before the 1 October date and before the rush that follows the first cold snap. Call the shop on (604) 727 4831, Monday to Friday between 9:00am and 5:30pm.
Can I leave winter tires on all year?
You can, but it is an expensive way to save a visit. The soft compound that grips in the cold wears rapidly above roughly 7°C, so a set left on through the summer can lose a season's life in a few warm months — and it gives up dry-road braking and steering response while it does. Swapping back in spring costs less than the tread it saves.
Regulations summarised from BC’s designated-highway winter tire rules. Signs on the route are the authority. Last reviewed 2026-09-01.