Lane splitting is legal in California and, as of August 2026, in only one other state. Four more states permit the narrower practice of lane filtering, where the traffic being passed must be stopped. California defines lane splitting in Vehicle Code section 21658.1 and sets no speed limit on it, despite what a great many articles claim.
B&D Injury Law Group represents injured motorcyclists across California. This article explains what California law actually says, which states permit splitting or filtering and under what conditions, and how the widely circulated speed figures came to be repeated as though they were law.
What California Law Says
Vehicle Code section 21658.1 was added by Assembly Bill 51 in 2016 and took effect on January 1, 2017. It has never been amended.
Subdivision (a) defines the practice: lane splitting means driving a motorcycle that has two wheels in contact with the ground between rows of stopped or moving vehicles in the same lane, including on both divided and undivided streets, roads, or highways.
Two things in that definition are worth noticing. It covers stopped or moving traffic, which is what makes California’s rule genuinely permissive rather than a filtering rule. And it applies on ordinary streets, not only on freeways.
Subdivision (b) says the California Highway Patrol may develop educational guidelines relating to lane splitting. Subdivision (c) directs the CHP to consult with the DMV, Caltrans, the Office of Traffic Safety, and a motorcycle safety organization in doing so. The authority is permissive and educational. It is not a grant of rulemaking power.
The Speed Rule That Does Not Exist
Search for California lane splitting and you will repeatedly encounter a rule: no more than 10 miles per hour faster than traffic, and never above 30 miles per hour. Those numbers are not in the law. Section 21658.1 contains no speed figure of any kind.
The history explains the confusion. As introduced, AB 51 would have imposed a 15 mph differential and a 50 mph ceiling. Those provisions were removed before passage and are not in the enacted statute. Separately, the CHP published educational guidelines in 2013 containing the 10 mph and 30 mph figures, and withdrew them in 2015 after a complaint that they amounted to an underground regulation issued without proper rulemaking. The CHP’s current public material offers general safety principles without numeric thresholds, noting that danger increases as the speed difference grows.
This is not a technicality. It changes what a rider is arguing about after a crash. There is no per se violation for splitting at a given speed. An insurer arguing that a rider broke the law by exceeding 10 mph over traffic is describing a withdrawn guideline, not a statute. What an adjuster or a defense expert can legitimately argue is that the speed was unreasonable under the circumstances, which runs through the basic speed law in Vehicle Code section 22350 or the unsafe lane change rule in section 22107, not through section 21658.1.
Splitting Versus Filtering
These two terms are used interchangeably in casual conversation and mean different things in law.
Lane splitting means passing between lanes of traffic that is still moving. Lane filtering means moving between vehicles that are stopped, typically advancing to the front at a red light. Every state that has legalized anything in this area has chosen one or the other, and most chose filtering.
Where It Is Legal, State by State
As of August 2026, six states permit some form of the practice.
| State | Statute | Effective | Type | Key conditions |
|---|---|---|---|---|
| California | Veh. Code § 21658.1 | Jan 1, 2017 | Splitting, stopped or moving | No numeric limits in the statute |
| Utah | Utah Code § 41-6a-704(6) | 2019 | Filtering | Two or more lanes same direction; speed limit 45 mph or less; overtaken vehicle stopped; motorcycle 15 mph or less |
| Montana | MCA § 61-8-392 | Oct 1, 2021 | Filtering, broadest | Motorcycle 20 mph or less; overtaken vehicle stopped or under 10 mph |
| Arizona | A.R.S. § 28-903(F) | 2022 | Filtering | Two or more adjacent lanes same direction; speed limit 45 mph or less; overtaken vehicle stopped; motorcycle 15 mph or less |
| Colorado | C.R.S. § 42-4-1503(3)(b) | Aug 7, 2024 | Filtering, strictest | Overtaken vehicle and adjacent-lane vehicles all stopped; pass on the left only; motorcycle 15 mph or less |
| Minnesota | Minn. Stat. § 169.974, subd. 5 | Jul 1, 2025 | Both | Splitting at 25 mph or less and no more than 15 mph over traffic; filtering at 15 mph or less |
Only California and Minnesota permit true lane splitting past moving traffic. Utah, Arizona and Colorado require the vehicle being passed to be stopped. Montana sits between, reaching vehicles moving up to 10 mph. Minnesota is the only state with a codified speed differential, which makes the persistent claim that California has one more curious.
Two Sunset Dates Riders Should Know
Two of these laws are written to expire unless renewed. Utah’s filtering provision is subject to repeal on July 1, 2027 under Utah Code section 63I-1-241, having already been extended once. Colorado’s SB 24-079 is set to repeal on September 1, 2027, pending a legislative review of a state transportation department report.
If you ride through either state after those dates, confirm the current status rather than relying on an article written earlier.
Hawaii Is Not on This List
Many listicles still include Hawaii for shoulder surfing. Hawaii prohibits lane splitting under HRS section 291C-153(c). A 2018 law authorized the state transportation department to designate specific shoulders where motorcycles might be permitted, and it expired under its own sunset clause on December 31, 2020. Motorcycles cannot use shoulders for regular travel in Hawaii today.
How This Affects a California Injury Claim
Because lane splitting is lawful in California, a rider who was splitting when struck has not committed a violation simply by splitting. That is the starting point, and it is a better starting point than riders in most states have.
What insurers argue instead is comparative fault. They will contend the rider was going too fast for conditions, moved unpredictably, or split through a gap that was closing. California follows pure comparative negligence under Li v. Yellow Cab Co. (1975) 13 Cal.3d 804, so a rider assigned a share of fault still recovers, reduced by that percentage. There is no threshold that cuts off recovery.
Drivers have obligations too. Vehicle Code section 22107 prohibits moving from a lane until the movement can be made with reasonable safety and after signaling. A driver who changes lanes into a splitting motorcyclist without signaling or checking a mirror has a section 22107 problem regardless of how the rider was positioned.
Evidence that helps a splitting case is often gone within days. Helmet camera and dashcam footage, nearby business and residential cameras, and the vehicles’ own event data recorders can establish relative speeds and lane positions far better than recollection can. Photograph lane positions and debris before vehicles are moved when it is safe to do so.
Is lane splitting legal in California?
Yes. Vehicle Code section 21658.1, effective January 1, 2017, defines lane splitting and makes it lawful. It covers riding between rows of stopped or moving vehicles in the same lane, on both divided and undivided roads.
Is there a speed limit for lane splitting in California?
No. Section 21658.1 contains no speed figure. The often-quoted 10 mph differential and 30 mph ceiling come from CHP educational guidelines that were withdrawn in 2015. Riding at an unsafe speed can still be addressed under the basic speed law in section 22350, but there is no lane-splitting speed statute.
Which states allow lane splitting or filtering?
Six as of August 2026. California and Minnesota allow lane splitting past moving traffic. Utah, Montana, Arizona and Colorado allow lane filtering, generally requiring the passed vehicle to be stopped or nearly stopped. Conditions and speed limits vary by state.
Can I still recover if I was lane splitting when I was hit?
Yes. Splitting is lawful in California, so it is not a violation on its own. An insurer may argue comparative fault based on speed or positioning, which reduces recovery by your percentage of fault but does not bar it.
Is lane splitting the same as lane filtering?
No. Splitting means passing between lanes of moving traffic. Filtering means advancing between vehicles that are stopped, such as at a red light. Most states that have legalized anything permit only filtering.
If you were injured while riding in California, the physical evidence and any video are worth securing quickly. Learn more about motorcycle accident claims, read about car accident cases, or contact B&D Injury Law Group for a free consultation.
This article is provided for general informational purposes only and does not constitute legal advice. Reading it does not create an attorney-client relationship. Every case is different and past results do not guarantee a similar outcome. If you have been injured, speak with a licensed attorney about your specific situation.