California’s car seat law is about to get significantly stricter — starting January 1, 2027, the state will require children under 10 to be in a child restraint in the rear seat, and kids ages 8–16 will need to pass the five-step seat belt fit test to ride without a booster. That’s the most aggressive expansion of any state law in the country right now. But even under the current 2026 rules, California already requires rear-facing until age 2 (one of the first states to mandate it) and a car seat or booster through age 8 or 4’9″. I’ve helped families across the Bay Area and the Central Valley navigate these requirements, and the biggest source of confusion is always the transition from harness to booster — parents move too early because their child “looks big enough.”
California recorded 3,807 traffic fatalities in 2024 — a 6.3% drop from 2023 and the lowest figure since 2019. Preliminary 2025 data shows an even more dramatic improvement, with a 49% decline in motor vehicle deaths through May compared to the same period in 2024. Despite the progress, California’s sheer volume of crashes (164,123 in 2024) means the risk on any given drive remains real.
This guide breaks down every requirement in California’s current child passenger safety law, previews the 2027 changes, explains the fines and enforcement rules, covers special situations, and answers the most common questions parents ask.
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California car seat laws by age (2026)
California’s child restraint statute (CVC § 27360–27368) has some of the most specific requirements in the country:
Rear-facing (birth to age 2): Children under 2 years old must ride in a rear-facing car seat. The only exceptions are if the child weighs 40 or more pounds OR is 40 or more inches tall. California was one of the first states to mandate rear-facing until age 2, aligning with AAP recommendations.
Forward-facing with harness (ages 2–8): After outgrowing the rear-facing position, children must remain in a child restraint system with a harness until they exceed the seat’s weight and height limits. Best practice is to keep children in a harnessed seat until the seat maxes out (typically 40–65 pounds) before moving to a booster.
Booster seat (until age 8 or 4’9″): Children under 8 who have outgrown a harnessed seat must use a belt-positioning booster seat. Once a child turns 8 OR reaches 4’9″ tall, they can use the vehicle’s seat belt alone.
Seat belt (age 8+ or 4’9″+): All passengers must wear a seat belt. Children 8 and older or 4’9″ and taller can use the vehicle’s lap-and-shoulder belt.
Back seat (under 13): California law doesn’t mandate the back seat for a specific age, but strongly recommends all children under 13 ride in the rear. Children in rear-facing seats must never be placed in front of an active airbag.
What’s changing in 2027
California Assembly Bill 435, signed into law, introduces major changes effective January 1, 2027:
Under 10 in the rear seat: Children under 10 must be properly secured in a rear seat in an appropriate child passenger restraint system.
Ages 8–16 seat belt fit test: Children ages 8 through 16 must pass the five-step seat belt fit test to ride without a booster seat. If the belt doesn’t fit properly, a booster is required regardless of age.
Higher fines: Violations could carry fines up to $490.
This makes California’s 2027 law the most protective child passenger safety statute in the nation. If you’re buying a car seat now, plan for the longer timeline.
If you’re not sure which seat fits your child’s current stage, our best-rated convertible car seats guide covers every transition from rear-facing infant through booster-ready child.
Fines and enforcement
Under current law, violating California’s child restraint requirements carries:
First offense: $100 fine (total cost with fees can exceed $350)
Subsequent offenses: $250 fine (total cost with fees can exceed $500)
California’s child restraint law is a primary enforcement law — an officer can pull you over solely for a child restraint violation.
The court may also order the offender to attend a child passenger safety education program.
Special situations
Taxis: California exempts taxis and limousines from child restraint requirements when the rear seat is occupied. However, children must still be secured in the back seat if available.
Rideshares (Uber/Lyft): Rideshare vehicles are not exempt from California’s child restraint law. If you’re traveling with a child, you must provide and install an appropriate car seat. Some rideshare services offer car-seat-equipped vehicles in select markets.
Leaving a child unattended in a vehicle: California’s Kaitlyn’s Law (Vehicle Code § 15620) makes it an infraction to leave a child 6 or younger unattended in a motor vehicle without the supervision of someone at least 12 years old. Penalties increase if the child suffers injury.
Smoking in a vehicle with children: California law (Health & Safety Code § 118948) prohibits smoking in a motor vehicle when a minor (under 18) is present. Violation is an infraction with a fine up to $100.
Car seat replacement after a crash: No state law requires it, but NHTSA and all major manufacturers recommend replacing any seat involved in a moderate-to-severe crash.
What to do if you get a ticket
1. Get the correct car seat immediately. California doesn’t offer automatic fine waiver for purchasing a seat, but demonstrating compliance can help at your court hearing.
2. Get it inspected. CHP offices statewide offer free car seat inspections. You can also find a certified technician through the NHTSA technician locator.
3. Attend a car seat safety class. The court may order this anyway, and voluntary attendance shows good faith.
If you need a free or low-cost car seat, check our guide to free car seats in California for verified programs across the state.
Frequently Asked Questions
When can my child sit in the front seat in California?
California recommends children under 13 ride in the back seat but doesn’t set a strict legal age for front-seat riding (except that children under 2 in rear-facing seats must be in the back). Starting in 2027, children under 10 will be required to ride in the rear seat.
What is the fine for a car seat violation in California?
First offense is a $100 base fine (total with fees often exceeds $350). Subsequent offenses carry a $250 base fine (total over $500). Starting in 2027, fines may reach $490.
Does California require rear-facing until age 2?
Yes — California was one of the first states to mandate rear-facing until age 2, with exceptions only for children who weigh 40+ pounds or are 40+ inches tall. Our best-rated convertible car seats include seats that rear-face well beyond these minimums.
Are taxis and Uber/Lyft exempt from car seat laws?
Taxis and limousines have a partial exemption when the rear seat is occupied. Rideshare vehicles (Uber, Lyft) are not exempt — you must provide a car seat when traveling with a child.
Can I use a secondhand car seat in California?
California doesn’t prohibit used car seats, but verify the seat hasn’t been in a crash, isn’t expired, isn’t recalled, and has all original parts. Check the NHTSA recall database before using any secondhand seat. Our guide on what to do with old car seats covers safe disposal.
Where can I get my car seat inspected in California?
CHP (California Highway Patrol) offices statewide offer free car seat inspections — call your local CHP office to schedule. Safe Kids California coalitions in Los Angeles, San Francisco, San Diego, Sacramento, and other cities also hold regular events. Find a certified CPS technician near you through NHTSA’s locator.
