Lane splitting is not legal in Idaho. Riding a motorcycle between lanes of slow or stopped traffic is a moving traffic infraction statewide, with no exception for congestion, highway type, or how slowly cars are moving. A citation carries a $90 fine, adds points to your driving record, and can gut your ability to recover damages if a crash follows.
What Idaho Law Says
Idaho has no statute that uses the words “lane splitting.” The prohibition comes from the general lane-use rule. Idaho Code § 49-637 requires every vehicle to be driven “as nearly as practicable entirely within a single lane” and not moved from that lane until the driver has first ascertained the movement can be made safely.1Idaho State Legislature. Idaho Code Title 49, Chapter 6, Section 49-637 – Driving on Highways Laned for Traffic Motorcycles are vehicles under Idaho law, so the rule applies to them in full.
The Idaho State Police has stated the point directly: lane splitting is “not permitted under Idaho law,” and motorcycles “are required to remain within a single marked lane unless making a legal lane change.”2Idaho State Police. Lane Splitting is Illegal in Idaho
Lane Filtering at Red Lights Is Also Illegal
Some states treat lane filtering, where a rider moves between vehicles that are fully stopped at an intersection, as a separate and allowed practice. Idaho does not. The Idaho STAR motorcycle safety program confirms that “lane sharing (lane splitting/filtering) with any other vehicle is illegal in Idaho.”3Idaho STAR. Motorcycle Laws
One narrow exception exists: two motorcycles may legally share a single lane side by side. A motorcycle cannot share a lane with a car, truck, or any other vehicle type.3Idaho STAR. Motorcycle Laws
Fine and License Points
A lane splitting stop produces a moving traffic infraction. Because the conduct isn’t separately listed, it falls under the “other moving traffic violations” line on Idaho’s infraction penalty schedule. For fiscal year 2026, the total is $90, covering the fixed penalty and court costs.4Idaho Judicial Branch. Infraction Penalty Schedule FY 2026
A conviction also adds points to your driving record. Moving violations not specifically listed in Idaho’s point schedule carry three points by default.5Cornell Law Institute. IDAPA 39.02.71.100 – Violation Point Count System Points stay on your record, accumulate across violations, and typically push insurance premiums higher at renewal.
What a Crash Costs You
The real financial danger isn’t the ticket. It’s what happens if a driver changes lanes into you while you’re splitting.
Idaho uses a modified comparative fault system under Idaho Code § 6-801. You can recover damages from another at-fault driver, but your recovery is reduced by your own share of fault, and if your fault equals or exceeds the other driver’s, you recover nothing.6Idaho State Legislature. Idaho Code Title 6, Chapter 8, Section 6-801 – Comparative Negligence or Comparative Responsibility
Because lane splitting is illegal in Idaho, the fact that you were doing it is strong evidence of negligence. An insurance adjuster or jury can assign a splitting rider a large percentage of the fault even when the driver who hit them did something wrong too. Push that number to 50 percent and the claim is dead. Riders who split lanes in Idaho are, in effect, betting their right to compensation on every mile.
How Other States Handle It
Idaho is in the majority. California is the only state that permits full lane splitting at highway speeds, under California Vehicle Code § 21658.1, which also authorizes the California Highway Patrol to develop safety guidelines.7California Legislative Information. California Vehicle Code 21658.1 – Lane Splitting
A smaller group of states, including Arizona, Utah, Montana, Colorado, and Minnesota, allows the narrower practice of lane filtering, generally capped at low speeds and limited to situations where surrounding traffic is stopped or nearly so. Idaho has not adopted any version of these laws, and the Idaho State Police continues to publicly reinforce that both splitting and filtering remain illegal here.2Idaho State Police. Lane Splitting is Illegal in Idaho If you’re riding into Idaho from a state that permits either practice, the legal protection stops at the state line.