Utah's traction law is a rule about equipment, switched on when a storm makes a road dangerous. It is not a calendar date. For drivers from Utah Valley heading to Park City, the Cottonwood Canyons or south toward Moab in winter, the practical question is whether your tires meet it and how you find out it is in effect.
Quick facts
| Vehicle | What UDOT lists as required when the law is active |
|---|---|
| AWD or 4WD | M/S, M+S or 3PMSF tires, or traction devices on at least 2 drive tires |
| 2WD car or light truck under 12,000 lb GVWR | At minimum 3PMSF tires; traction devices on all drive tires also acceptable |
| Over 12,000 lb GVWR | Traction devices on all drive tires |
| Class 3 segments, including the Cottonwood Canyons | Acceptable tires with 5/32 inch tread or traction devices |
Source: UDOT's Snow Tire, Chain and Traction Device Requirements page, read Nov. 2, 2026. The governing rule is Utah Administrative Code R920-6.
How you find out it's on
UDOT says the requirement is posted by road signs, message boards, the UDOT traffic app and its social media. It also warns: "Be prepared, you may be required to be in compliance up to 24 hours before a storm." A 2025 UDOT release tied the 24-hour advance enforcement in the Cottonwood Canyons to HB 196. UDOT lists current restrictions at udottraffic.utah.gov/roadrestrictions.
What changed in the Cottonwood Canyons
A Nov. 13, 2025 UDOT release described a stricter Class 3 designation for Big and Little Cottonwood Canyons, a 5/32 inch tread requirement, citations by law enforcement (Cottonwood Heights and Sandy City police, with the Salt Lake County Sheriff's Office supporting roadside and parking enforcement) and a free voluntary tire-inspection sticker program at more than 140 tire shops from Nov. 13 to Feb. 28, 2026. Our Little Cottonwood traction law guide covers ski-season specifics.
Tire markings
M/S and M+S mean mud and snow. 3PMSF is the mountain-and-snowflake symbol on the sidewall, which UDOT treats as the stronger standard for two-wheel-drive vehicles. Check the sidewall before you drive, not on the shoulder.
What we could not confirm
The UDOT pages we read did not give a fine amount, a commercial chain-up season or a list of every canyon route. UDOT's map of routes where traction devices are required is linked from its requirements page, so look at it for the stretch you will drive.
From Provo
If you are driving our canyons, start with winter tires and canyon driving in Utah, then check the Alpine Loop closure before heading up American Fork Canyon. For longer winter trips, see Zion in winter and our ranking of Utah national parks by season.
Who should skip the drive
If a storm is forecast and you have two-wheel drive on all-season tires without 3PMSF markings, wait for the roads to clear or carry chains you have practiced fitting.
Frequently Asked Questions
When does Utah's traction law apply?
What do AWD and 4WD vehicles need?
What do two-wheel-drive cars need?
What about heavier vehicles?
Is there a tread-depth rule?
Can police write tickets for it?
How do I check if the law is active?
Do I need winter tires to drive Provo Canyon?
Sources
The facts in this guide were checked against these sources. Hours, fees and rules change, so confirm anything time-sensitive with the source before you go. How we make Provo.com.
- Snow Tire, Chain & Traction Device Requirements, UDOT. Checked November 2, 2026.
- Cottonwood Canyons traction law expands to improve canyon safety, UDOT. Checked November 2, 2026.
- UDOT: Traction Law, UDOT. Checked November 2, 2026.
