All weather vs all season tires: which do you need?

Jump to: M+S vs 3PMSF · Side by side · Which type fits my climate? · Trade offs · Winter tire rules · One set or two? · Shopping checklist

The real difference is on the sidewall

The names sound alike and tire ads blur them, so start with the markings. M+S (mud and snow) comes from a U.S. Tire Manufacturers Association (USTMA) definition based on tread design features such as groove and void area. It does not require the tire to pass any snow traction test, which is why Canada’s CAA says tires marked only M+S are not winter tires.

The 3PMSF symbol, a three peak mountain with a snowflake inside, is different. Under USTMA’s severe snow definition, a tire may carry it only after reaching a minimum snow traction index against a standard reference tire in a packed snow test. Dedicated winter tires carry it, and so do all weather tires. That one symbol is what separates an all weather tire from an ordinary all season tire.

Consumer Reports describes all weather tires as a subset of all season tires: they still sit in the all season, SUV all season and similar categories, but with tread and rubber tuned for cold and snow. Look for the symbol on the exact size you buy, since markings can vary across sizes in one model line.

All weather vs all season vs winter, side by side

Question	All season	All weather	Dedicated winter
Typical sidewall marks	M+S; usually no 3PMSF	M+S plus 3PMSF	3PMSF (often M+S too)
Passed a snow traction test?	Usually not	Yes, packed snow test vs a reference tire	Yes, same test; designed well beyond it
Stays on all year?	Yes	Yes	No; swap off in spring
Cold weather grip	Fades as temperatures drop toward freezing	Better in cold, slush and snow	Best, especially on ice and in deep cold
Hot, dry handling	Good; performance all seasons are sharper	Usually a little softer than a comparable all season	Not designed for summer use
Tread life	Often the longest warranties	Varies by model; check UTQG and warranty	Shorter if run in warm months
Legal winter tire in Quebec (Dec 1 to Mar 15)?	No, unless it carries 3PMSF	Yes, with the 3PMSF pictogram	Yes
Best for	Mild winters, rare snow, or drivers who can wait for plowed roads	Regular snow but mostly moderate cold; one set all year	Frequent ice, deep snow, mountain passes, long deep cold

Which tire type fits my climate?

Answer three quick questions. This runs only in your browser and stores or sends nothing.

How often is there snow or slush on roads you must drive?Almost neverA few days a winterRegularly through winterMost winter days, or deep snow

How cold do your winters get?Rarely below freezingOften around freezingLong spells well below freezing, regular ice

Will you store and swap a second set each season?No, I want one setYes, that is fine

Can you stay home until roads are plowed?No, I have to driveUsually yes

A rough guide only, based on the general guidance in the sources below. Local laws, your vehicle maker and a trained tire professional take priority.

Trade offs to know before you switch

• Snow grip vs ice grip. The 3PMSF test is run on packed snow. It says nothing about glare ice, so an all weather tire is not a substitute for a studless winter tire where ice is a weekly event. See our winter tires guide for when dedicated winter tires make sense.
• Not every all weather tire is equal. Consumer Reports notes that some all weather models performed well in its tests while others are best avoided, so compare independent results for the specific model.
• Wear and warranty. Snow focused tread and compounds can trade away some tread life. Compare the UTQG treadwear grade and the mileage warranty, and remember that winter traction drops as tread wears; BC requires at least 3.5 mm of tread for a legal winter tire. Our tread depth guide shows how to measure it.
• Price. Consumer Reports says some all weather tires cost more than the all season tires they replace, but most buyers come out ahead by skipping a second set and the seasonal changeovers.
• Fit four, keep them matched. Whatever you choose, use the same type on all four wheels. Mixing all season and all weather tires front to rear can upset handling in snow. See mixing tires.
• Pressure drops with temperature. Check pressure monthly when tires are cold, and more often as fall turns to winter. Our cold tire pressure guide explains how.

Winter tire rules that treat these tires differently

Most U.S. states do not require winter tires, but chain or traction rules can apply on mountain routes, and Canada is stricter:

• Quebec. From December 1 to March 15 inclusive, vehicles registered in Quebec must run tires marked with the mountain and snowflake pictogram, or studded tires. Fines run from $200 to $300 plus costs. An M+S only all season tire does not comply; an all weather tire with 3PMSF does.
• British Columbia. On signed highways during the winter tire period, a legal winter tire needs at least 3.5 mm of tread and either the M+S mark or the 3PMSF symbol. The province notes that 3PMSF tires, which include all weather tires, offer better traction on snow and ice and recommends them for cold weather driving.
• Transport Canada advises that tires with the pictogram meet specific snow traction performance requirements and recommends four matching winter tires.

If you drive into Canada or over mountain passes in winter, check the rules for every area on your route before you go.

One set of all weather tires or two sets?

Running all season tires in summer and winter tires in winter means two sets of tires, often a second set of wheels, a place to store the off season set, and two changeovers a year. You do get the best tire for each season, and each set wears only part of the year. A single set of all weather tires removes the swaps and storage but asks one tire to do every job reasonably well. If you go the two set route, our seasonal tire storage guide covers how to store the off season set so it ages well.

Shopping checklist

1. Confirm size, load index and speed rating on your door placard; see our load index and speed rating guide.
2. Look for the 3PMSF symbol on the exact size if you want an all weather tire, not just M+S.
3. Compare independent test results for the specific model, plus UTQG treadwear and the mileage warranty.
4. Check the DOT date code so you are not sold old stock.
5. Buy four and have them installed by a licensed professional.

For an example of how we review a popular all weather tire, see our research based Michelin CrossClimate2 review. We do not road or lab test tires.

Informational only, not professional, safety or legal advice. Your vehicle maker, tire maker, local law and a trained tire technician take priority over this page.