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Compliance · Updated Oct 2026

Chain laws by state: when you carry, when you chain up

Every state runs chain law its own way. Some make you carry chains for months on set routes. Others only care once the signs go up. Most fines are about not having chains, or not putting them on when you're told to.

This page covers the 9 western states first. Each row links to the state's own DOT page or statute. When we couldn't confirm a fine on an official page, it says "Check state source." Before you climb, check the live road-conditions link for that state.

Carry seasons are already running in some states. Colorado's started Sept 1, Montana's started Oct 1, and Washington's starts Nov 1.

Carry, count, levels

  • Carry means you need chains in the truck, even on dry pavement, during the season or on the listed routes.
  • Count is how many tires get chained when the law is in effect.
  • Levels are the posted steps. They don't match from state to state, so read each state's row on its own.
A rust top edge means that state's carry season is running now. Chains ride in the truck, dry road or not.

CO

Colorado

Sept 1 to May 31, carry chains on 7 mountain corridors, including I-70 west of Morrison. Source: SB24-100 / C.R.S. 42-4-106 (opens in a new tab)

Fine: Not chaining up, up to $500 + $79. Stuck and blocking, $1,000 + $157. Not carrying: check state source. (CSP) (opens in a new tab)

Colorado control levels

Colorado control levelsPassenger Vehicle Traction Law. Commercial Vehicle Chain Law (4 drive tires; buses 2). Passenger Vehicle Chain Law (all vehicles).Passenger Vehicle Traction LawCommercial Vehicle Chain Law (4 drive tires; buses 2)Passenger Vehicle Chain Law (all vehicles)
Colorado steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: SB24-100 / C.R.S. 42-4-106.
Carry seasonSept 1–May 31, 7 mtn corridors
Applies toCMVs over 16,000 lb GVWR/GCWR in commerce, or carrying 16+ passengers
Routes
  • I-70 west of MP 259 (Morrison)
  • CO-9 MP 63–97 (Frisco–Fairplay)
  • US-40 west of MP 256 (Empire)
  • US-50 west of MP 225 (Salida)
  • US-160 west of MP 304 (Walsenburg)
  • US-285 west of MP 250 (Morrison)
  • US-550 MP 0–130
Chain countChains or ATDs on 4 drive tires (all drive tires if fewer than 4); buses 2 drive tires
Levels
  • Passenger Vehicle Traction Law
  • Commercial Vehicle Chain Law (4 drive tires; buses 2)
  • Passenger Vehicle Chain Law (all vehicles)
AlternativesAlternative traction devices (ATDs)
StatuteC.R.S. 42-4-106(5)(a)(I)(C), as amended by SB24-100 (eff. Aug 7, 2024)

Check before you climb: COtrip (opens in a new tab)

Sources

  1. Colorado State Patrol: Chain law information  (opens in a new tab)
  2. SB24-100 session law amending C.R.S. 42-4-106  (opens in a new tab)
  3. CDOT: What must be carried (PDF)  (opens in a new tab)

Checked 2026-10-16

WA

Washington

Nov 1 to Apr 1, carry chains on designated passes, plus 2 extra chains in the truck. Source: WSDOT (opens in a new tab)

Fine: Up to $500. (WSDOT Winter Driving Guide) (opens in a new tab)

Washington control levels

Washington control levelsTraction tires advised. Traction tires required (chains on vehicles over 10,000 GVWR). Chains required, all vehicles except AWD/4WD. Chains required on all vehicles.Traction tires advisedTraction tires required (chains on vehicles over 10,000 GVWR)Chains required, all vehicles except AWD/4WDChains required on all vehicles
Washington steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: WSDOT.
Carry seasonNov 1–Apr 1, posted passes + 2 spares
Applies toVehicles and combinations over 10,000 lb GVWR
Routes
  • I-90 MP 32–101
  • I-82 MP 3–26
  • SR-97 MP 145 – Jct SR-2
  • SR-2 MP 36–108
  • SR-12 MP 135–187
  • SR-97 MP 0–59
  • SR-410 Enumclaw–Naches
  • SR-20 MP 262–342 and MP 120–192
  • SR-155 MP 45–79
  • SR-970 MP 0–10
  • SR-14 MP 18–108.4
  • SR-542 MP 22.91–57.26
Chain countBy axle count when posted (WSDOT chart); always carry 2 extra chains
Levels
  • Traction tires advised
  • Traction tires required (chains on vehicles over 10,000 GVWR)
  • Chains required, all vehicles except AWD/4WD
  • Chains required on all vehicles
AlternativesTwo-sided hardened-metal chains (no plastic), cable chains, ATDs on WSP approved list
StatuteWAC 204-24-050

Check before you climb: WSDOT pass reports (opens in a new tab)

Sources

  1. WSDOT: Chain requirements for vehicles over 10,000 lb  (opens in a new tab)
  2. WAC 204-24-050  (opens in a new tab)
  3. WSDOT Winter Driving Guide (PDF)  (opens in a new tab)

Checked 2026-10-16

OR

Oregon

No set season. By law, carry chains on highway sections posted with a carry sign. ODOT advises carrying them whenever road conditions might require them. Source: ORS 815.142 (opens in a new tab), ODOT (opens in a new tab)

Fine: Not chaining a CMV, $880 presumptive (ORS 815.140). Not carrying where posted: check state source.

Single-drive trucks over 10,000 GVW already chain at level 2.

Oregon control levels

Oregon control levelsCarry chains or traction tires. Chains: single-drive over 10,000 GVW and lighter towing vehicles. Chains: all towing or over 10,000 GVW. Chains or traction tires on all vehicles.Carry chains or traction tiresChains: single-drive over 10,000 GVW and lighter towing vehiclesChains: all towing or over 10,000 GVWChains or traction tires on all vehicles
Oregon steps up as the weather turns. The rust step is the one where your drive tires get chained. Single-drive trucks over 10,000 GVW already chain at level 2. Source: ORS 815.142.
Carry seasonWhere posted (carry sign); ODOT: carry when conditions may require
Applies toOver 10,000 lb GVW; carry on highway sections posted with a carry sign (ORS 815.142)
Routes
  • All highways statewide
Chain countPer OAR 734-017-0010 (e.g., tandem-drive tractor + trailer: two tires each side of primary drive axle, plus one tire on the trailer front axle and one on a rear axle)
Levels
  • Carry chains or traction tires
  • Chains: single-drive over 10,000 GVW and lighter towing vehicles
  • Chains: all towing or over 10,000 GVW
  • Chains or traction tires on all vehicles
AlternativesCheck state source
StatuteORS 815.140, 815.142, 815.145; OAR 734-017

Check before you climb: TripCheck (opens in a new tab)

Sources

  1. ODOT: Tips for commercial vehicle drivers  (opens in a new tab)
  2. ODOT: Chains and traction tires  (opens in a new tab)
  3. ORS 815.142: Failure to carry traction tires or chains  (opens in a new tab)

Checked 2026-10-17

CA

California

No carry season, but trucks without chains get turned back at screening. Source: Caltrans (opens in a new tab)

Fine: VC 27459, $25 base, $193 total bail. Counties can vary. (Judicial Council) (opens in a new tab)

California control levelsCaltrans/CHP shorthand, not sign text

California control levelsR-1. R-2. R-3. Truck screening (must show chains). Caltrans/CHP shorthand, not sign text.R-1R-2R-3Truck screening (must show chains)
California steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: Caltrans.
Carry seasonNo season; screened at checkpoints
Applies toHeavy-duty vehicles over 6,500 lb must chain whenever controls are posted; trucks without chains are turned back at screening
Routes
  • No designated list; commonly I-5 north of Redding, I-80 Donner, US-50 Echo Summit, SR-58 Tehachapi, I-15 Cajon, I-5 Tejon
Chain count13 CCR 1072: 2-axle truck 2 drive tires; 3-axle truck or tractor 4 drive tires; semitrailer 2 tires on rear-most axle; super singles all drive tires
Levels
  • R-1
  • R-2
  • R-3
  • Truck screening (must show chains)

Caltrans/CHP shorthand, not sign text

AlternativesTire traction devices per CVC 605, incl. cable, textile and automatic chains; ATD-only trucks may need added chains
StatuteCVC 605, 27450–27503; 13 CCR 1072

Check before you climb: QuickMap (opens in a new tab)

Sources

  1. Caltrans: Truck chain requirements  (opens in a new tab)
  2. Caltrans: Chain control status chart  (opens in a new tab)
  3. Judicial Council: Uniform Bail and Penalty Schedule  (opens in a new tab)

Checked 2026-10-16

NV

Nevada

Full-sized trucks and tractors pulling a combination carry one set per powered wheel during the season when chains may be needed. There are no fixed dates. Source: NAC 484D.420 (opens in a new tab)

Fine: Check state source.

Nevada control levels

Nevada control levelsChains or Snow Tires Required (over 10,000 GVW: chains on drive wheels and trailer braking wheels). Chains Required, except 4WD with M-S tires.Chains or Snow Tires Required (over 10,000 GVW: chains on drive wheels and trailer brakingwheels)Chains Required, except 4WD with M-S tires
Nevada steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: NAC 484D.420.
Carry seasonCombos: 1 set/powered wheel, in season
Applies toCarry: full-sized trucks/truck-tractors in a combination, one set of chains per powered wheel (NAC 484D.420(5)). Use: over 10,000 lb must use chains when posted.
Routes
  • Wherever posted
Chain countDrive axles; trailers with brakes chain the braking axle; one set per semitrailer
Levels
  • Chains or Snow Tires Required (over 10,000 GVW: chains on drive wheels and trailer braking wheels)
  • Chains Required, except 4WD with M-S tires
AlternativesCable chains (may be restricted); NDOT-approved fabric/plastic alternative traction devices
StatuteNRS 484D.515–484D.525; NAC 484D.420(5)

Check before you climb: Nevada 511 (opens in a new tab)

Sources

  1. NDOT: Traction and chain requirement descriptions  (opens in a new tab)
  2. NAC 484D.420  (opens in a new tab)

Checked 2026-10-16

ID

Idaho

No carry rule. Chains go on only when ITD posts them on Lookout, Fourth of July or Lolo pass. Source: Idaho Code 49-948 (opens in a new tab)

Fine: Check state source.

Idaho control levels

Idaho control levelsPosted chain requirement on Lookout, Fourth of July or Lolo pass.Posted chain requirement on Lookout, Fourth of July or Lolo pass
Idaho steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: Idaho Code 49-948.
Carry seasonNone
Applies toCommercial vehicles, when ITD posts chains on the listed passes
Routes
  • I-90 Lookout Pass
  • I-90 Fourth of July Pass
  • US-12 Lolo Pass
Chain countOne tire each side of one drive axle + one axle at/near rear of each towed vehicle
Levels
  • Posted chain requirement on Lookout, Fourth of July or Lolo pass
AlternativesAny device with traction equal to or better than chains
StatuteIdaho Code 49-948(5)–(9)

Check before you climb: 511 Idaho (opens in a new tab)

Sources

  1. Idaho Code 49-948  (opens in a new tab)

Checked 2026-10-16

MT

Montana

Oct 1 to Apr 30, towing units 26,001 lb and up carry chains in designated areas. Source: MDT (opens in a new tab)

Fine: Not carrying, $225 first offense, then $225 to $500. Not chaining: check state source.

4WD exemption: MCA 61-9-436.

Montana control levels

Montana control levelsChains / traction equipment required (posted).Chains / traction equipment required (posted)
Montana steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: MDT.
Carry seasonOct 1–Apr 30, 26,001+ lb towing (4WD exempt)
Applies toTowing units 26,001 GVW or more (not 4WD)
Routes
  • 29 designated locations (see MDT table)
Chain countTowing units: drive wheels of one axle
Levels
  • Chains / traction equipment required (posted)
AlternativesAutoSock approved
StatuteMCA 61-9-406, 61-9-436

Check before you climb: 511MT (opens in a new tab)

Sources

  1. MDT: Montana tire and chain laws  (opens in a new tab)

Checked 2026-10-16

WY

Wyoming

No carry rule. At Level 2, CMVs chain at least 2 drive wheels on the same axle. Source: WYDOT (opens in a new tab)

Fine: Up to $250, or up to $750 if it closes all lanes in one or both directions.

Wyoming control levels

Wyoming control levelsLevel 1: chains, adequate snow tires or AWD. Level 2: chains, or AWD with M+S/all-weather tires; CMVs chain 2 drive wheels.Level 1: chains, adequate snow tires or AWDLevel 2: chains, or AWD with M+S/all-weather tires; CMVs chain 2 drive wheels
Wyoming steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: WYDOT.
Carry seasonNone
Applies toAll vehicles when restriction posted
Routes
  • Specific highway sections when posted
Chain countLevel 2: at least two drive wheels at opposite ends of the same drive axle
Levels
  • Level 1: chains, adequate snow tires or AWD
  • Level 2: chains, or AWD with M+S/all-weather tires; CMVs chain 2 drive wheels
AlternativesCheck state source
StatuteW.S. 31-5-956(e), (j)

Check before you climb: WYDOT 511 (opens in a new tab)

Sources

  1. WYDOT: Chain law  (opens in a new tab)
  2. WYDOT: Travel restriction statute (W.S. 31-5-956)  (opens in a new tab)

Checked 2026-10-16

UT

Utah

No carry rule. When the Traction Law is on, trucks over 12,000 lb need devices on all drive tires. Source: UDOT (opens in a new tab)

Fine: Check state source.

UDOT sets Traction Law by segment class (Class I/II). Check UDOT for the roads.

Utah control levels

Utah control levelsClass I segment: vehicles over 12,000 GVW traction-device equipped. Class II segment: all vehicles traction devices or 4WD.Class I segment: vehicles over 12,000 GVW traction-device equippedClass II segment: all vehicles traction devices or 4WD
Utah steps up as the weather turns. The rust step is the one where your drive tires get chained. Source: UDOT.
Carry seasonNone
Applies toVehicles over 12,000 GVWR when the Traction Law is in effect (possibly up to 24 h before a storm)
Routes
  • See UDOT Winter Chains Required Routes Map
Chain countTraction devices on all drive tires; one tire per dual set is enough
Levels
  • Class I segment: vehicles over 12,000 GVW traction-device equipped
  • Class II segment: all vehicles traction devices or 4WD
AlternativesChains, cables, snow socks, studs, sand distribution devices
StatuteUtah Admin. Code R920-6; Utah Code 41-6a-1636

Check before you climb: UDOT Traffic (opens in a new tab)

Sources

  1. UDOT: Snow tire, chain & traction device requirements  (opens in a new tab)
  2. UDOT motor carriers: R920-6 text  (opens in a new tab)

Checked 2026-10-16