Lane Filtering vs. Lane Splitting in Colorado: What’s Legal and What Riders Need to Know

Motorcycle fatalities remain a serious concern across Colorado, and nowhere is that more evident than in El Paso County, which continues to record more motorcycle deaths than any other county in the state.

For a region with thousands of riders, military veterans, commuters, and working families who rely on motorcycles for transportation and recreation, these statistics deserve attention. Since Colorado legalized lane filtering in 2024, many riders and drivers have struggled to understand the difference between lane filtering and lane splitting. That confusion has led to misconceptions about what is legal, what is safe, and what can lead to a crash.

This guide explains the difference between lane filtering and lane splitting, reviews Colorado’s current motorcycle laws, and addresses some of the most common myths surrounding these practices.

Motorcycle Fatalities Remain a Serious Concern in Colorado

Recent statistics highlight the risks motorcyclists continue to face on Colorado roads:

• 165 motorcyclists were killed statewide in 2024, the highest number ever recorded.
• 148 motorcyclists lost their lives in 2025, remaining near historic highs.
• Motorcycles account for approximately 3% of registered vehicles but nearly 24% of all traffic fatalities.
• Motorcycle deaths have increased roughly 57% since 2015.
• Approximately 60% of rider fatalities occur between Memorial Day and Labor Day.

While lane filtering has received significant public attention since becoming legal, law enforcement officials continue to identify speeding, alcohol impairment, and lack of protective gear as leading contributors to fatal motorcycle crashes.

Understanding the Difference Between Lane Filtering and Lane Splitting

Many people use the terms “lane filtering” and “lane splitting” interchangeably, but under Colorado law they are very different.

What Is Lane Filtering?

Lane filtering allows a motorcyclist to move between rows of stopped vehicles under specific conditions.

Colorado legalized lane filtering through Senate Bill 24-079, which took effect on August 7, 2024. Under the law, a motorcyclist may filter between vehicles only when:

• Traffic in the rider’s lane and adjacent lanes is completely stopped.
• The motorcycle is traveling 15 miles per hour or less.
• The rider passes on the left side of stopped vehicles.
• The roadway provides enough space to pass safely.
• The rider does not enter oncoming traffic.

Importantly, lane filtering is optional. Riders are never required to filter through traffic.

The current law is scheduled to expire on September 1, 2027, while the Colorado Department of Transportation completes a study evaluating its impact on roadway safety.

What Is Lane Splitting?

Lane splitting occurs when a motorcyclist rides between vehicles that are still moving.

Unlike lane filtering, lane splitting remains illegal in Colorado. If traffic is moving, even slowly, motorcyclists must remain within their designated lane.

This distinction is critical because many riders mistakenly assume the legalization of lane filtering also legalized lane splitting. It did not.

Common Myths About Lane Filtering and Lane Splitting

Misunderstandings about Colorado’s motorcycle laws continue to create confusion among both riders and drivers.

Myth: Lane Filtering and Lane Splitting Are the Same Thing

Reality: Lane filtering involves passing stopped vehicles at 15 mph or less. Lane splitting involves traveling between moving vehicles and remains illegal in Colorado.

Myth: Lane Filtering Is Still Illegal

Reality: Lane filtering became legal in Colorado on August 7, 2024, under Senate Bill 24-079.

Myth: Riders Can Filter Whenever Traffic Is Slow

Reality: Traffic must be fully stopped. Slow-moving traffic does not qualify.

Myth: Riders Are Required to Lane Filter

Reality: The law permits lane filtering but does not require it. Riders should only filter when they believe it can be done safely.

Myth: Lane Filtering Is Causing Colorado’s Increase in Motorcycle Deaths

Reality: Colorado law enforcement officials have not identified lane filtering as a primary cause of rising motorcycle fatalities. Speeding, alcohol use, and other high-risk behaviors continue to be the most significant contributing factors.

Why These Rules Matter

Motorcyclists are far more vulnerable than occupants of passenger vehicles. A minor mistake that results in property damage for two cars can cause catastrophic injuries for a rider.

One of the most common statements heard after a motorcycle crash is, “I never saw the motorcycle.”

Motorcycles are smaller, less visible, and often harder for drivers to judge accurately. As a result, many serious crashes occur at:

• Intersections
• Left-turn crossings
• Lane changes
• Merging areas

These are locations where drivers frequently fail to notice an approaching motorcycle before making a maneuver.

Responsibilities of Drivers and Riders Under Colorado Law

Colorado law recognizes that both drivers and motorcyclists have responsibilities on the road.

Motorcycles are entitled to the full use of a traffic lane. Drivers should never attempt to crowd a rider or force a motorcycle out of its lane.

Drivers must also ensure that any lane change can be completed safely before moving into another lane. Failing to verify that a lane is clear before changing lanes can result in liability if a collision occurs.

Tips for Drivers

• Check mirrors and blind spots carefully for motorcycles.
• Exercise extra caution at intersections and left turns.
• Signal lane changes early and verify that the lane is clear.
• Give motorcyclists adequate space.
• Allow legally filtering motorcycles room to pass stopped traffic safely.

Tips for Motorcyclists

• Follow all lane filtering requirements.
• Never lane split in moving traffic.
• Avoid lingering in vehicle blind spots.
• Increase visibility through proper lane positioning.
• Ride defensively and anticipate unexpected driver behavior.

Determining Fault After a Motorcycle Accident

When a motorcycle crash occurs, the focus is rarely on labels such as “filtering” or “splitting.” Instead, investigators and insurance companies examine whether each party acted reasonably and followed the law.

Colorado follows a comparative fault system, meaning responsibility may be divided among multiple parties based on their actions.

Research consistently shows that drivers are responsible for many multi-vehicle motorcycle collisions because they fail to detect or properly yield to riders. However, every accident is unique, and fault depends on the specific facts of the crash.

Injured in a Motorcycle Accident? Know Your Rights

A serious motorcycle accident can leave victims dealing with painful injuries, mounting medical bills, lost income, and uncertainty about the future.

Understanding your legal rights should not add to that burden.

For nearly three decades, Heuser & Heuser, L.L.P. has represented injured individuals throughout Colorado Springs, Pueblo, and Southern Colorado. Our team understands the unique challenges motorcyclists face after an accident and works to help clients pursue the compensation they need to move forward.

If you or a loved one has been injured in a motorcycle accident, contact Heuser & Heuser, L.L.P. for a free consultation. There is no fee unless we recover compensation on your behalf.

Disclaimer: This article is provided for informational purposes only and does not constitute legal advice. Laws may change, and every case is different. For legal advice regarding your specific situation, consult a licensed Colorado attorney.