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

Idaho has no law that names lane splitting, and none that allows it. The rule that governs it is Idaho Code 49-637(1), which requires every vehicle on a highway with two or more clearly marked lanes to "be driven as nearly as practicable entirely within a single lane." Motorcycles get no exception, and Idaho State Police say lane splitting, lane filtering and lane sharing are all illegal in Idaho. For how other states handle 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 Idaho state law: the laned-highway rule in Idaho Code 49-637, the passing rules in 49-632 and 49-633, the motorcycle riding rule in 49-665, the speed rule in 49-654, the reckless and inattentive driving statute in 49-1401, the infraction rules in 49-236, 49-1501, 49-1503 and 18-113A with the Idaho Supreme Court's infraction penalty schedule, the reckless driving suspension in 49-326, the Idaho State Police statement on lane splitting, and the 2025 filtering proposal RS 32400. It does not cover city or county ordinances, insurance consequences, or the law of other states.

What Idaho law says about riding between lanes

Idaho's rules of the road are in Title 49, chapter 6 of the Idaho Code. That chapter has no section that authorizes lane splitting or lane filtering, and no section that prohibits it by name. Its motorcycle section, 49-665, deals only with seats and passengers: it says a person operating a motorcycle "shall ride only upon the permanent and regular seat attached to it," and limits when a passenger may ride.

The rule that applies instead is the general one for laned highways. Idaho Code 49-637 reads:

"Whenever any highway has been divided into two (2) or more clearly marked lanes for traffic the following, in addition to all else, shall apply: (1) A vehicle shall be driven as nearly as practicable entirely within a single lane and shall not be moved from that lane until the driver has first ascertained that the movement can be made with safety."

A motorcycle ridden on the line between two lanes of cars is not "entirely within a single lane." Section 49-637 contains no exception for motorcycles and none for stopped or slow traffic, and it has not been amended since it was added in 1988.

Splitting, filtering, lane sharing and shoulders

What Idaho State Police say

Idaho State Police addressed the question directly in a release titled "Lane Splitting is Illegal in Idaho," dated May 30, 2025:

"lane splitting is illegal in Idaho. Lane splitting, the practice of riding a motorcycle between lanes of slow-moving or stopped traffic, is not permitted under Idaho law. Neither is lane filtering or lane sharing with other vehicles. Motorcycles, like all vehicles, are required to remain within a single marked lane unless making a legal lane change."

That release is an agency statement, not a statute. It matches the text of 49-637(1), and it shows how the state police read the law.

Passing on the right and using the shoulder

Idaho limits passing on the right for every vehicle, including motorcycles. Idaho Code 49-633 says:

"(1) The driver of a vehicle may overtake and pass upon the right of another vehicle only under the following conditions: (a) When the vehicle overtaken is making or about to make a left turn; (b) Upon a highway with unobstructed pavement of sufficient width for two (2) or more lines of vehicles moving lawfully in the direction being traveled by the overtaking vehicle. (2) The driver of a vehicle may overtake and pass another vehicle upon the right only under conditions permitting such movement in safety. That movement shall not be made by driving off the roadway."

Subsection (1)(b) allows ordinary passing in another lane on a multi-lane highway. It does not allow riding between the lanes, which 49-637(1) still governs. The last sentence of subsection (2) rules out using the shoulder or any area off the roadway to get past traffic on the right. Idaho Code 49-119(19) defines the roadway as the part of a highway used for vehicle travel, "exclusive of sidewalks, shoulders, berms and rights-of-way," so a shoulder is off the roadway.

Passing on the left has its own rule. Under Idaho Code 49-632(1), a driver overtaking another vehicle "shall pass to the left at a safe distance and shall not again drive to the right side of the roadway until safely clear of the overtaken vehicle."

What happens if you are caught lane splitting in Idaho

There are three levels of consequence: an infraction for breaking a lane, passing or speed rule; the misdemeanor of inattentive driving; and the more serious misdemeanor of reckless driving. Neither misdemeanor statute mentions lane splitting. Each applies only when the riding meets that statute's own elements.

The infraction. Breaking a chapter 6 rule is an infraction unless a statute says otherwise (Idaho Code 49-236(2)), and 49-1501 lets a peace officer issue an Idaho uniform citation "for any infraction violation of the provisions of chapters 3, 4 and 6 through 9 of this title." The lane rule (49-637) and the passing rules (49-632 and 49-633) are in chapter 6. Under 49-1503(2) and 18-113A, an infraction "is punishable only by a penalty not exceeding three hundred dollars ($300) ... and no imprisonment," in the amount set by statute or, failing that, the fixed penalty in Idaho Infraction Rule 9 as of January 1, 2014. The Idaho Supreme Court's infraction penalty schedule effective July 1, 2025 has no separate row for lane-use or passing violations; its category for "Other Moving Traffic Violations" lists a $33.50 fixed penalty, or $90.00 with court costs.

Speed. Speed rules apply on top of the lane rule. Idaho Code 49-654(1) says "No person shall drive a vehicle at a speed greater than is reasonable and prudent under the conditions and having regard to the actual and potential hazards then existing," even below the posted limit. Section 49-654(2)(b) lets a motorcycle exceed the posted limit by up to 15 mph while passing a slower vehicle, but only when passing on the left on a two-lane road posted at 55 mph or more, or when passing in a passing lane. It does not cover riding between lanes. The same court schedule lists speeding 1 to 15 mph over the limit at a $33.50 fixed penalty ($90.00 with court costs) and 16 mph or more over at $98.50 ($155.00).

Inattentive driving. Idaho Code 49-1401(3) makes inattentive driving "a lesser offense than reckless driving." It applies "where the conduct of the operator has been inattentive, careless or imprudent, in light of the circumstances then existing, rather than heedless or wanton, or in those cases where the danger to persons or property by the motor vehicle operator's conduct is slight." It is a misdemeanor punishable by up to 90 days in jail, a fine of up to $300, or both.

Reckless driving. The way a rider splits lanes can meet the elements of Idaho Code 49-1401(1). That statute applies to a person who drives or is in actual physical control of a vehicle on a highway:

"carelessly and heedlessly or without due caution and circumspection, and at a speed or in a manner as to endanger or be likely to endanger any person or property"

Both parts are required: careless or heedless driving, and a speed or manner that endangers or is likely to endanger a person or property. Under 49-1401(2), a first reckless driving conviction is a misdemeanor, and the person "may be sentenced to jail for not more than six (6) months or may be fined not more than one thousand dollars ($1,000), or may be punished by both fine and imprisonment." A conviction after a prior reckless driving conviction within five years is a misdemeanor punishable by up to one year in jail, a fine of up to $2,000, or both.

Reckless driving also reaches the license. Under Idaho Code 49-326(1)(f), where the court has not ordered a suspension, the Idaho Transportation Department may suspend driving privileges for 30 days after a reckless driving conviction, 90 days for a second conviction within two years of the first, and one year for a third within three years of the first.

Has Idaho tried to legalize lane filtering?

Yes, once, without success. On February 17, 2025, Representative Skaug presented RS 32400 to the House State Affairs Committee. According to the committee minutes, the draft would have added a new section of the Idaho Code "to allow responsible motorcycle lane filtering which permits motorcycles to travel between traffic lanes, wherein said lanes are traveling the same direction." The allowance would have applied "only" on roadways "with a speed limit of over 50 m.p.h. and with speed limitations on the motorcycles passing between lanes."

The minutes record the result: "Due to the lack of a motion, RS 32400 was returned to the sponsor." Idaho has not adopted a filtering law, and 49-637 contains no filtering exception.

Federal law and lane splitting

Lane use is set state by state. The federal motorcyclist safety grant rule, 23 CFR 1300.25, sets criteria for rider training and motorist awareness programs and says nothing about lane splitting or filtering, so Idaho's own code controls.

If a crash happens

Whether a rider was splitting or filtering can come up after a collision, but it is one fact among many in a fault and injury claim. For how fault, insurance and filing deadlines work, see our guide to Idaho motorcycle accident laws. For crash rules that apply to every driver, see Idaho car accident laws.

Related pages

• Lane splitting laws by state
• Idaho motorcycle accident laws
• Idaho car accident laws
• Utah lane splitting laws
• Oregon lane splitting laws

This article provides general legal information about Idaho law, not legal advice. For advice about a specific situation, contact a lawyer licensed in Idaho or the Idaho State Police.

Last updated: 2026-10-08.

Frequently Asked Questions

Is lane splitting legal in Idaho?

No statute allows it. Idaho Code 49-637(1) requires a vehicle to be driven as nearly as practicable entirely within a single lane on a marked multi-lane highway, with no motorcycle exception, and Idaho State Police say lane splitting is illegal in Idaho.

Is lane filtering legal in Idaho?

No law authorizes it. Section 49-637(1) has no exception for stopped traffic, and Idaho State Police stated in May 2025 that lane filtering is not permitted under Idaho law.

Did Idaho pass a lane filtering law?

No. A 2025 draft, RS 32400, would have allowed filtering on roads with speed limits over 50 mph, but it was returned to its sponsor in the House State Affairs Committee on February 17, 2025, for lack of a motion.

Can motorcycles ride on the shoulder in Idaho?

Not to pass. Idaho Code 49-633(2) allows passing on the right only in safety and says the movement shall not be made by driving off the roadway.

What is the fine for lane splitting in Idaho?

A lane-use or unsafe-passing violation is an infraction. Under Idaho Code 49-1503(2) and 18-113A it carries no jail and a penalty capped at $300, and the Idaho Supreme Court's schedule effective July 1, 2025 lists other moving traffic violations at a $33.50 fixed penalty, or $90.00 with court costs. Riding that meets the elements of reckless or inattentive driving is a misdemeanor with higher penalties.

Can lane splitting be reckless driving in Idaho?

It can if the riding is careless and heedless and endangers, or is likely to endanger, a person or property under Idaho Code 49-1401(1). A first conviction is a misdemeanor punishable by up to six months in jail, a fine of up to $1,000, or both, and a repeat within five years by up to one year, $2,000, or both. Riding that is inattentive, careless or imprudent rather than heedless or wanton, or that causes only slight danger, can instead be inattentive driving under 49-1401(3), a misdemeanor punishable by up to 90 days in jail, a fine of up to $300, or both.