Is Lane Splitting Legal in Colorado? Filtering Rules (2026)

Lane splitting through moving traffic is illegal in Colorado, but lane filtering past stopped traffic is allowed for two-wheeled motorcycles until September 1, 2027. C.R.S. 42-4-1503(3)(a) bars riding between lanes or between rows of vehicles, and C.R.S. 42-4-1503(3)(b), added by Senate Bill 24-079, carves out a narrow exception for passing stopped vehicles at 15 mph or less. For how other states treat the same maneuvers, see our guide to lane splitting laws by state.

Information last verified on 2026-10-08. This article has not been reviewed by a licensed lawyer.

Jurisdiction scope: This article covers Colorado state law: the motorcycle lane rules in C.R.S. 42-4-1503 (including the lane filtering authorization in subsection (3)(b) and its repeal date), the enacting act SB 24-079, the general rule on passing on the right in C.R.S. 42-4-1004, and the traffic infraction penalty schedule in C.R.S. 42-4-1701. It does not cover municipal ordinances, license points, insurance consequences, or the law of other states.

Splitting, filtering, shoulders and riding two abreast

These terms describe different maneuvers, and Colorado treats them differently.

The statute itself does not use the word "filtering." Section 42-4-1503(3)(b) describes the maneuver as the driver of a two-wheeled motorcycle overtaking or passing another motor vehicle in the same lane as the motorcycle.

The general ban on riding between lanes

The starting point is a flat prohibition. C.R.S. 42-4-1503(3)(a) reads:

"(3) (a) A person shall not drive a motorcycle or autocycle between lanes of traffic or between adjacent lines or rows of vehicles."

A companion rule in 42-4-1503(2) says the driver of a motorcycle or autocycle "shall not overtake or pass in the same lane occupied by the vehicle being overtaken." Both rules stay in force. The filtering provision is an exception that applies "notwithstanding" them, and only when its conditions are met.

Colorado also protects a rider's lane space. Under 42-4-1503(1), "All motorcycles are entitled to full use of a traffic lane, and no motor vehicle shall be driven in such a manner as to deprive any motorcycle of the full use of a traffic lane." That subsection does not apply to motorcycles operated two abreast in a single lane.

When lane filtering is allowed

Senate Bill 24-079 added the filtering exception. The act was approved on April 4, 2024, and the amended section took effect on August 7, 2024. The core text, C.R.S. 42-4-1503(3)(b)(I), reads:

"(b) (I) Notwithstanding subsections (2) and (3)(a) of this section, the driver of a two-wheeled motorcycle may overtake or pass another motor vehicle in the same lane as the motorcycle if: (A) The overtaken or passed motor vehicle is stopped; (B) The motor vehicles in the adjacent lanes, if the lanes are for the same direction of travel as the lane occupied by the two-wheeled motorcycle, are stopped; (C) The driver of the two-wheeled motorcycle is on a road with lanes wide enough to pass safely; (D) The passing motorcycle is driving at fifteen miles per hour or less; and (E) Conditions permit prudent operation of the motorcycle while overtaking or passing."

The five conditions are joined by "and," so a rider needs all of them at once. Filtering past a vehicle that is still rolling, at more than 15 mph, or in a lane too narrow to pass safely falls outside the exception and back under the general ban.

The exception also ends the moment traffic moves. Under 42-4-1503(3)(b)(II), "When the motor vehicles that are being overtaken or passed by the two-wheeled motorcycle begin moving, the driver of the motorcycle shall cease overtaking or passing a motor vehicle pursuant to subsection (3)(b)(I) of this section."

Where filtering is never allowed

Even when all five conditions are met, 42-4-1503(3)(b)(III) bars filtering in three places:

• On the right shoulder.
• To the right of a vehicle in the farthest right-hand lane, if the highway is not limited access.
• In a lane of traffic moving in the opposite direction.

Two-wheeled motorcycles only

The exception applies to "the driver of a two-wheeled motorcycle." The general ban in 42-4-1503(3)(a) names both motorcycles and autocycles, so an autocycle driver has no filtering exception.

The filtering rule ends on September 1, 2027 unless extended

The filtering authorization is a dated rule. C.R.S. 42-4-1503(3)(b)(IV) states: "This subsection (3)(b) is repealed, effective September 1, 2027." Unless the General Assembly extends it before then, the exception lapses on that date and the general ban in 42-4-1503(3)(a) and the same-lane rule in 42-4-1503(2) are what remain.

The law also builds in a review. Under 42-4-1503(3)(c)(I), the Colorado Department of Transportation "shall analyze data on the safety effects of subsection (3)(b) of this section and issue a report to the general assembly by January 1, 2027." That reporting requirement is itself repealed effective July 1, 2028. Riders who rely on filtering should check the status of 42-4-1503 before September 1, 2027.

Penalties for illegal lane splitting

Under C.R.S. 42-4-1503(6), "Any person who violates any provision of this section commits a class A traffic infraction." That covers splitting between moving vehicles, filtering without meeting every condition, filtering on the shoulder, and riding more than two abreast.

The penalty schedule in C.R.S. 42-4-1701(4) lists section 42-4-1503 under motorcycle violations at a $30.00 penalty and a $6.00 surcharge. For class A traffic infractions generally, 42-4-1701(3)(a)(I) sets a penalty range of $15 to $100. The schedule figures are the penalty and surcharge only; license points and any other costs are outside this page.

Police officers in the performance of their official duties are exempt from subsections (2) and (3) of the section under 42-4-1503(5).

If a filtering or splitting maneuver leads to a crash

Whether a rider followed 42-4-1503 is one fact in a crash claim; it does not settle fault by itself. For how fault, insurance and deadlines work after a motorcycle crash, see our guide to Colorado motorcycle accident laws. For the broader rules that apply to vehicle crashes in the state, see Colorado car accident laws.

Related pages

• Lane splitting laws by state
• Colorado motorcycle accident laws
• Colorado car accident laws

This article provides general legal information about Colorado law, not legal advice. For advice about a specific situation, contact a lawyer licensed in Colorado or the Colorado Department of Transportation.

Last updated: 2026-10-08.

Frequently Asked Questions

Is lane splitting legal in Colorado?

No, not between moving vehicles. C.R.S. 42-4-1503(3)(a) bars driving a motorcycle between lanes of traffic or between adjacent lines or rows of vehicles; the only exception is lane filtering past stopped traffic under 42-4-1503(3)(b).

Is lane filtering legal in Colorado?

Yes, for two-wheeled motorcycles, until September 1, 2027. C.R.S. 42-4-1503(3)(b) allows it only when the passed vehicle and same-direction vehicles in the adjacent lanes are stopped, the lanes are wide enough, the motorcycle goes 15 mph or less, and conditions permit prudent operation.

How fast can you lane filter in Colorado?

Fifteen miles per hour or less, under C.R.S. 42-4-1503(3)(b)(I)(D). The traffic being passed must also be stopped, and the rider must stop filtering when it begins moving.

When does Colorado's lane filtering law expire?

C.R.S. 42-4-1503(3)(b)(IV) repeals the filtering authorization effective September 1, 2027. Unless the General Assembly extends it, the general ban in 42-4-1503(3)(a) is what remains after that date.

Can motorcycles ride on the shoulder to pass traffic in Colorado?

No. C.R.S. 42-4-1503(3)(b)(III)(A) bars filtering on the right shoulder, and C.R.S. 42-4-1004(2), which applies to every vehicle, says passing on the right shall in no event be made by driving off the pavement or main-traveled portion of the roadway. A 42-4-1004 violation is a class A traffic infraction listed in 42-4-1701 at a $100 penalty and a $10 surcharge.

Can an autocycle lane filter in Colorado?

No. The filtering exception in C.R.S. 42-4-1503(3)(b) applies to the driver of a two-wheeled motorcycle, and the general ban in (3)(a) covers both motorcycles and autocycles.

What is the ticket for illegal lane splitting in Colorado?

Violating C.R.S. 42-4-1503 is a class A traffic infraction under 42-4-1503(6). The penalty schedule in C.R.S. 42-4-1701 lists the section at a $30 penalty and a $6 surcharge.

Can two motorcycles ride side by side in Colorado?

Yes. C.R.S. 42-4-1503(4) prohibits operating motorcycles more than two abreast in a single lane, so two abreast is within the rule.