Understanding Colorado Chain Laws: Do They Apply To Cars?

Colorado's Chain Law requires all commercial vehicles to carry chains when travelling on I-70 between the Dotsero and Morrison exits from September 1 to May 31. This law also applies to smaller vehicles, including passenger cars and trucks with two-wheel and four-wheel drive, weighing less than 16,001 pounds. These vehicles must have tire chains or alternative traction devices (ATDs) installed on two or more tires. The Chain Law is enforced to ensure safe driving and prevent traffic delays or road closures caused by vehicles losing traction on snowy roads.

Passenger Vehicle Traction Law

Colorado's Chain Law applies to all vehicles, including passenger vehicles, and came into effect in 1996. The law requires motorists to be prepared for driving in winter conditions and to have adequate tires and equipment.

The Passenger Vehicle Traction Law requires motorists to have either an all-wheel or four-wheel-drive vehicle, or, for two-wheel-drive vehicles, snow tires or all-weather tires with a mud/snow designation. The minimum tread depth for all tires must be at least 3/16" and vehicles that do not meet these criteria must carry chain devices or alternative traction devices. The law applies to all motorists when weather conditions require it and motorists will be alerted to an active Traction Law by highway signage, COtrip.org, and traffic/roadway condition alerts.

The Traction Law is always active from September 1 to May 31 on I-70 from Dotsero to Morrison. The law was updated in 2019 to alleviate delays and crashes during the peak winter driving season.

The Passenger Vehicle Chain Law is the final safety measure before a highway is closed. When this law is in effect, every vehicle must have chains or an approved alternative traction device. Motorists driving without the required equipment when a Traction Law or Chain Law is in effect could be fined more than $130 and more than $650 for blocking the roadway.

Passenger Vehicle Chain Law

The Passenger Vehicle Chain Law is a safety measure implemented by the Colorado Department of Transportation (CDOT) during severe winter storms. It requires motorists to have tire chains or alternative traction devices (ATDs) installed on two or more drive tires. This law applies to all vehicles weighing less than 16,001 pounds gross vehicle weight rating (GVWR) and is in effect on I-70 from Dotsero to Morrison from September 1 to May 31.

Requirements

When the Passenger Vehicle Chain Law is in effect, every vehicle must have chains or an approved alternative traction device on two or more drive tires. This includes passenger vehicles, crossovers, SUVs, and small trucks. The requirement to use chains or ATDs is in addition to the minimum tire tread depth requirement of 3/16" for all vehicles in Colorado.

Notifications and Alerts

Motorists will be notified of an active Passenger Vehicle Chain Law through various channels. These include large message boards and fixed highway signs along the highway, as well as electronic variable message roadway signs. Additionally, CDOT utilizes radio channels, the official CDOT travel website (cotrip.org), phone message systems, emails, texts, and other automated personal notification systems.

Penalties for Non-Compliance

Motorists driving with inadequate equipment when a Passenger Vehicle Chain Law is in effect could face fines. The fine for non-compliance is over $130, and if a motorist blocks the roadway due to inadequate equipment, the fine increases to more than $650.

Safe Winter Driving in Colorado

Safe winter driving in Colorado requires preparation. This includes checking weather conditions, understanding your vehicle's capabilities, and ensuring your vehicle is equipped with the necessary tires and equipment. It is important to follow the traction and chain laws to ensure your safety and the safety of other motorists on the road.

Commercial Vehicle Chain Law

The Commercial Vehicle Chain Law applies to all commercial vehicles travelling on I-70 between the Dotsero exit (mile point 133) and the Morrison exit (mile point 259) from September 1 to May 31. Commercial vehicles are defined as those used in commerce to transport passengers or property, with a gross combination weight rating of 16,001 or more pounds, inclusive of a towed unit with a gross vehicle weight rating of more than 10,000 pounds. This law also applies to vehicles with a gross vehicle weight rating of 16,001 or more pounds, as well as those designed to transport 16 or more passengers, including the driver.

On all other roadways in Colorado, commercial vehicles are required to put chains on their tires when the Colorado Department of Transportation (CDOT) puts the Chain Law into effect. This is usually in response to winter storms or hazardous road conditions. When the Chain Law is in effect, commercial vehicles must put chains or alternate traction devices (ATDs) on at least four of their drive wheel tires, or all of their drive wheel tires if the vehicle has fewer than four. Buses are required to chain or have ATDs on at least two drive wheel tires.

The Commercial Vehicle Chain Law is important for safety and traffic flow. Without chains, vehicles can lose traction, causing traffic delays and sometimes road closures. Compliance with this law helps commercial vehicles traverse steep climbs and ensures the safety of everyone on the road.

To ensure compliance, the Colorado Department of Transportation (CDOT) notifies the public of travel restrictions through various channels. This includes electronic message boards and fixed signs along the highway, as well as notifications on the cotrip.org website and through other communication channels like radio and text messages. Failure to comply with the Commercial Vehicle Chain Law can result in fines ranging from $500 to $1,157, depending on the impact on traffic flow.

It is important for commercial drivers to be aware of the Commercial Vehicle Chain Law and take the necessary steps to comply. This includes carrying sufficient chains and being prepared for winter driving conditions, especially on mountainous roads with steep grades. By following these regulations, commercial drivers can help ensure their safety and the safety of other motorists on Colorado's roads during the winter season.

Winter driving conditions

Chain Law and Traction Law

Colorado's Chain Law and Traction Law apply to all vehicles, not just large commercial vehicles. These laws can be put into effect at any time for all types of vehicles.

The Chain Law requires motorists to have tire chains or alternative traction devices (ATDs) installed on two or more drive tires. This is the final safety measure before the highway is closed. When the Chain Law is active, it will be posted on large message boards along the highway and on fixed signs.

The Traction Law requires two-wheel-drive passenger vehicles to have all-weather or mud and snow-rated tires with adequate tread, or to affix chains or ATDs. Four/all-wheel-drive vehicles must have all drive wheels engaged and tires with adequate tread depth.

Commercial Vehicle Chain Law

The Commercial Motor Vehicle Chain Law applies to all large vehicles, regardless of whether they are used for private or commercial purposes. Commercial vehicles with a gross combined weight rating of 16,001 lbs or more are required to have four or more drive wheels covered with an appropriate traction device. Vehicles with fewer than four drive wheels must have all drive wheels covered with an appropriate traction device. Buses must chain or have ATDs on two drive wheel tires.

Passenger Vehicle Traction and Chain Laws

The Passenger Vehicle Traction Law and Chain Law apply to all vehicles that weigh less than 16,001 pounds, including crossovers, SUVs, and small trucks.

During a Traction Law, all motorists are required to have either:

• 4WD or AWD vehicle and 3/16” tread depth
• Tires with a mud and snow designation (M+S icon) and 3/16” tread depth
• Winter tires (mountain-snowflake icon) and 3/16” tread depth
• Tires with an all-weather rating by the manufacturer and 3/16” tread depth
• Chains or an approved alternative traction device

The Passenger Vehicle Chain Law requires motorists to have tire chains or ATDs installed on two or more drive tires.

Penalties

Motorists driving with inadequate equipment when a Traction Law or Chain Law is in effect could be fined more than $130. If a motorist blocks the roadway because they have inadequate equipment, they could be fined more than $650.

Chain Law restrictions

Colorado's Chain Law applies to all vehicles, not just large commercial vehicles. All vehicles need to be equipped with adequate tires and equipment when travelling in Colorado during the winter. Chain Law and safe tire requirements can be put into effect at any time for all types of vehicles.

Larger Vehicles, Including Recreational and Commercial Motor Vehicles

As of August 7, 2024, all commercial motor vehicle drivers must carry chains from September 1 to May 31. This applies to vehicles with a combined weight of more than 16,000 lbs used in commerce or as transport for at least 16 passengers (including the driver) on public highways. Commercial vehicles and buses have a larger footprint on roadways where chains are required.

Smaller Vehicles, Including Passenger Cars and Trucks with Two-Wheel and Four-Wheel Drive

All two-wheel-drive motor vehicles with a GCWR/GVWR less than 16,001 pounds travelling on any portion of I-70 between mile point 259 (Morrison) and mile point 133 (Dotsero) from September 1 through May 31 must have:

• Tire chains for two or more drive tires
• An approved ATD for two or more drive tires
• Tires with a tread depth of at least 3/16-inch and which are rated for either “All weather” or “Mud and Snow” (indicated by a “All Season”, M+S, M/S, etc. on the sidewall) by the manufacturer. This is indicated on the side of the tire by “M+S”, “M/S” or an icon of a mountain with a snowflake.

All four-wheel-drive motor vehicles less than 16,001 pounds travelling on any portion of I-70 between mile point 259 (Morrison) and mile point 133 (Dotsero) from September 1 through May 31 must have tires with a tread depth of at least 3/16-inch and be adequate for winter driving conditions.

Passenger Vehicle Traction Law

The passenger traction law requires two-wheel-drive passenger vehicles to have all-weather or mud and snow-rated tires with adequate tread or to affix chains or alternate traction devices (ATDs). Four/all-wheel-drive vehicles must have all drive wheels engaged and tires with adequate tread depth.

Passenger Vehicle Chain Law

The Passenger Vehicle Chain Law imposes the most restrictive requirements during inclement weather. All passenger vehicles must have chains or alternate traction devices (ATDs) on two or more drive tires. This applies to every two/four/all-wheel-drive passenger vehicle in the affected area.

Commercial Vehicle Chain Law

The Commercial Motor Vehicle Chain Law is a requirement for all large vehicles to affix chains or alternate traction devices (ATDs) to all drive tires (up to four). Even though it has "commercial" in the name, the requirement is based on the Gross Vehicle Weight Rating (GVWR) or Gross Combined Weight Rating (GCWR) for the vehicle regardless of its use (private or commercial).

Frequently asked questions