California Bicycle Laws

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

Confirm equipment fit with the helmet size calculator before relying on an age rule alone.

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

A bell does not replace yielding or signaling, but it can warn other path users; compare bike bells and horns.

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

If alcohol or drugs may impair the rider, do not ride; arrange another way home and secure the parked bike with a lock suited to the theft risk.

— Not yet researched.

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

For equipment that matches the visibility requirement, compare bike lights by beam and runtime.

— Not yet researched.

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

For low-light road and group visibility, compare bike lights for commuting and unlit roads.

Rule

One ear only

Statute

¹

A mirror can supplement direct observation but cannot replace shoulder checks or hearing traffic; compare bike mirrors by mount type.

— Not yet researched.

Bicycle registration required

No

Operator license required

No

For theft prevention when the bike is parked, compare bike locks for different risk levels.

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.

For low-light road and group visibility, compare bike lights for commuting and unlit roads.