California's primary slower-traffic keep-right rule is found in Vehicle Code §21654.
A vehicle traveling at a speed slower than the normal flow of traffic moving in the same direction generally must be driven in the right-hand lane available for traffic, or as close as practicable to the right-hand edge or curb.
The rule does not prevent a driver from using another lane while overtaking and passing another vehicle or while preparing for a lawful left turn.
California DMV guidance reinforces the same principle. Drivers who choose to travel slower than surrounding traffic are advised to use the right lane, and when another driver is close behind and wishes to travel faster, the slower driver should move to the right.
On multilane roads, the California Driver's Handbook describes the far-left lane as the passing lane and advises drivers to use the left lane to pass or turn left.
California also has special turnout rules on some two-lane roads. A slow-moving vehicle must use a designated turnout area or lane to allow following vehicles to pass when passing is unsafe and five or more vehicles are following behind.
Exceptions
- Overtaking and passing another vehicle traveling in the same direction.
- Preparing for a lawful left turn.
- Using another lane when roadway conditions, traffic controls or lane configuration require it.
- Using designated lanes such as HOV or other special-use lanes when legally permitted.
Penalties
Violating California's keep-right or lane-use rules may result in a traffic citation. The total amount due can include the base fine, penalty assessments, court fees and other charges.
Because the final amount can vary by county and by the specific violation charged, drivers should verify the amount shown on the citation or with the court handling the case.
Official Source
Last verified: October 10, 2026