Truck chain laws by state
Which states make trucks carry chains, when you must chain up, and what it costs if you don't. Every rule below comes from a state DOT, state patrol, legislature or administrative-code page, linked on each state page and checked 2026-10-29. If an official page we checked doesn't give a detail, we say so instead of guessing.
Dated carry seasons: Colorado, September 1–May 31 (16,001 lb+ on listed corridors). Washington, November 1–April 1 (over 10,000 lb GVWR on designated routes). Montana, October 1–April 30 (26,001 lb+ towing a trailer on designated passes).
| State | Type | Carry season | Fine |
|---|---|---|---|
| Colorado | Must carry chains (dated or standing rule) | September 1 through May 31 every year (C.R.S. 42-4-106(5)(a)(I)(C)). The current corridor list took effect August 7, 2024. | Up to a $500 fine plus a $79 surcharge for not complying with winter driving restrictions; $1,000 plus a $157 surcharge if you are stuck and blocking a travel lane (Colorado State Patrol). CDOT says failing to carry chains can bring a $500 fine. |
| California | Chain up when posted | None. Caltrans: "California does not have any specific dates when vehicles are required to carry chains." | Not stated in the official sources we checked. Confirm with the state. |
| Oregon | Must carry chains (dated or standing rule) | No fixed dates on the official pages we checked. ODOT: carry chains "whenever road conditions might require their use or Snow Zone signs are posted." | Class C traffic violation; for a motor vehicle registered under ORS chapter 826 (apportioned/commercial) it is a specific-fine violation with a presumptive fine of $880 (ORS 815.140). Failing to carry chains where signs require carrying them is a Class C traffic violation (ORS 815.142). |
| Washington | Must carry chains (dated or standing rule) | November 1 to April 1: chains must be carried at all times on designated routes. April 2 to October 31: only when posted (WSDOT). | Traffic infraction with a $500 penalty including all statutory assessments (RCW 47.36.250(4)). |
| Nevada | Chain up when posted | Not stated in the official sources we checked. Confirm with the state. | Not stated in the official sources we checked. Confirm with the state. |
| Idaho | Chain up when posted | None in statute; ITD may set the requirement "at any time" conditions are unsafe (Idaho Code 49-948(5)). | Not stated in the official sources we checked. Confirm with the state. |
| Montana | Must carry chains (dated or standing rule) | October 1 through April 30 (MCA 61-9-436). Chains can be required year-round when MDT posts them (MCA 61-9-406). | Failing to carry: $225 for a first offense; $225 to $500 for later offenses (MCA 61-9-436(2)). Penalty for not chaining when posted: Not stated in the official sources we checked. Confirm with the state. |
| Utah | Chain up when posted | No fixed dates on UDOT's pages. Compliance may be required up to 24 hours before a storm (UDOT). | Not stated in the official sources we checked. Confirm with the state. |
| Wyoming | Chain up when posted | None in statute; restrictions apply when signs (including electronic signs) are posted (W.S. 31-5-956(e)). | Misdemeanor, up to $250; up to $750 if the violation causes an incident closing all lanes in one or both directions (W.S. 31-5-956(j)). |
| Arizona | No requirement found | None found. | None found. |
| New Mexico | No requirement found | Not stated in the official sources we checked. Confirm with the state. | Not stated in the official sources we checked. Confirm with the state. |
State summaries
Colorado truck chain law
Commercial vehicles 16,001 lb and up must carry chains or alternate traction devices on listed mountain corridors from September 1 through May 31, whatever the weather.
California truck chain law
No calendar carry rule. When chain controls are posted, every heavy-duty vehicle over 6,500 lb must mount chains, snow tires or not, and Caltrans may turn back trucks without chains at screening points.
Oregon truck chain law
Commercial vehicles over 10,000 lb GVW must carry chains whenever conditions might require them or Snow Zone signs are posted, and must chain up when signs say so. Fine for commercial vehicles: $880 presumptive.
Washington truck chain law
Vehicles over 10,000 lb GVWR must carry chains on designated routes from November 1 to April 1, plus at least two extra chains. Ignoring a posted chain requirement is a $500 infraction.
Nevada truck chain law
When chain signs are posted, vehicles over 10,000 lb must use tire chains (snow tires do not count) on the driving wheels and the braking wheels of the trailer.
Idaho truck chain law
On Lookout Pass and Fourth of July Pass (I-90) and Lolo Pass (US 12), ITD can require chains on commercial vehicles when conditions are unsafe, never on bare pavement.
Montana truck chain law
From October 1 through April 30, trucks of 26,001 lb GVW or more towing a trailer must carry approved traction devices in designated chain areas. $225 fine for a first offense.
Utah truck chain law
When UDOT activates the traction law on a route, vehicles over 12,000 lb GVWR must have chains, cables, socks or studs on all drive tires (one tire per dual set).
Wyoming truck chain law
When WYDOT posts a chain restriction, commercial vehicles must chain at least two drive wheels at opposite ends of the same drive axle. Up to $250, or $750 if you close the road.
Arizona truck chain law
No truck chain-carry or chain-control statute found. Arizona law only permits chains when needed for safety.
New Mexico truck chain law
We did not find an official New Mexico chain-carry or chain-control rule for trucks. Treat this as unverified and watch posted signs.
Live chain controls change by the hour. Check the state's 511 or road-conditions site before you climb, and follow posted signs and officers even if they differ from this page. Rules are current as of 2026-10-29. Not legal advice.