
California Bicycle Laws
Last reviewed by BikeSize EditorialAn overview of California's bicycle laws, reviewed and cited to primary sources. Use the sections below to jump to a specific rule, or the Sources block at the end for the full citation list.
This guide is for general information only and is not legal advice. Laws change - verify current rules with your state DOT or a licensed attorney before relying on this for any legal matter. Read full disclaimer.
Helmet rules
- Required under age
- Required under age 18
- Applies to passengers
- Yes
- Standard
- CPSC
- Penalty
- Fine of up to $25 for a first offense; courts often waive or reduce the fine on proof of helmet purchase and completion of a bicycle-safety course.
- Statute
- 1
See our find your helmet size and kids bike sizing guide.
Sidewalk riding
- Statewide rule
- Defers to local rules
- Notes
- No statewide rule. Cal. Veh. Code § 21206 expressly authorises cities and counties to regulate bicycle operation on sidewalks. San Francisco prohibits sidewalk riding by anyone aged 13 or older (S.F. Transp. Code § 7.2.12); Los Angeles permits it except where it endangers pedestrians; San Diego bans it in business districts. Always check the local municipal code.
- Statute
- 1
See our commuter bike sizing guide and bike fitting guide.
DUI on a bicycle
- Applies to bicycles
- Yes
- Separate cycling DUI statute
- Yes
- BAC limit
- —
- Penalty
- California prosecutes cycling under the influence under a separate statute (CVC § 21200.5) rather than the standard auto DUI law (CVC § 23152). Maximum fine of $250 with no jail time. The offense is not a DUI conviction, so it does not trigger an automatic driver-licence suspension; courts may, however, refer riders under 21 to the DMV for a discretionary licence review.
- Statute
- 1
Hand signals
— Not yet researched.
Lights & reflectors
- Front light required
- Yes
- Front spec
- White lamp on the front, visible from a distance of 300 feet to the front and from the sides of the bicycle.
- Rear requirement
- Rear reflector or light
- Rear spec
- Red reflector - or a solid or flashing red light with a built-in reflector - on the rear, visible from 500 feet when directly in front of lawful upper-beam headlamps. Side reflectors are required on each side: white or yellow forward of center, red or white rear of center. Pedal reflectors (white or yellow) are required on the front and back of each pedal, or equivalent reflective material on the rider's shoes or ankles.
- Side reflectors
- Yes
- Pedal reflectors
- Yes
- When required
- Darkness
- Statute
- 1
See our bike lights that meet the law and winter and low-light cycling setup.
Bike-lane rules
— Not yet researched.
Group riding & two-abreast
- Two abreast allowed
- Yes
- Conditions
- California has no statutory two-abreast cap for bicycles. The general lane-position rule under Cal. Veh. Code § 21202 ('as close as practicable to the right-hand curb') applies; group rides commonly default to single file in narrow lanes and two abreast where the lane is wide enough to share.
- Statute
- 1
Headphones & earbuds
- Rule
- One ear only
- Statute
- 1
Child passengers
— Not yet researched.
Registration & licensing
- Bicycle registration required
- No
- Operator license required
- No
Highways & interstates
- Interstates
- Varies by segment
- Notes
- Cal. Veh. Code § 21960 authorises Caltrans and local authorities to prohibit pedestrians, bicycles, and motor-driven cycles on any freeway or expressway by sign. In practice, every urban Interstate segment in California is signed prohibited; many rural Interstate shoulders (notably parts of I-5, I-8, I-10, I-15, I-40, and I-80) are signed open. Always check the Caltrans bicycle-on-freeways map for the specific corridor before riding.
Sources
One size question, fifty answers
Find the right bike (and helmet) size for your rider
State helmet and child-passenger rules cover what you must wear. Our calculators cover what will actually fit.
Open the kids bike size calculator