California Child Car Seat Laws

California Car Seat Law Requirements by Age and Size

CA car seat laws require children to use a child restraint system that matches their age, height, and weight. Depending on a child’s stage, that may mean a rear-facing car seat, a forward-facing car seat with a harness, or a booster seat before moving to the vehicle’s safety belt.

The legal requirements are primarily found in California Vehicle Code Sections 27360 and 27363, which establish child passenger restraint rules based on a child’s age and size. Car seat laws apply whenever a child is transported in a motor vehicle, whether the trip is across town or on a longer highway drive. Because child restraint laws can change, these statutes should be reviewed before relying on them for legal compliance.

Stage One: Rear-Facing Car Seats

Children under 2 years old must travel in a rear-facing car seat except if they are 40 pounds or more or at least 40 inches tall. Even after a child becomes eligible to ride forward-facing, many convertible car seats allow extended rear-facing use, and pediatric safety organizations encourage keeping children rear-facing until they reach the seat’s maximum height or weight limit.

California ties the rear-facing rule to age, weight, and height rather than to the seat model, so the statutory floor and the manufacturer’s limits are two separate things to check. Parents and caregivers should follow the manufacturer’s instructions to decide when a child has outgrown a given seat, and treat the statutory thresholds as the minimum. Vehicle Code Section 27363 adds one absolute limit: a rear-facing restraint may never be used in a front seat with an active passenger airbag.

Stage Two: Forward-Facing Harness Seats

Once a child grows beyond the rear-facing limits of their car seat, they may graduate to a forward-facing seat with a five-point harness. California law does not establish a specific age or weight for moving from a harnessed seat to a booster seat. Instead, families should continue using the harness until the child reaches the manufacturer’s maximum height or weight limit.

Stage Three: Booster Seats

Children who have outgrown a forward-facing harness but are not yet large enough for the vehicle safety belt use a booster seat. Under Vehicle Code Section 27360, a child under 8 must be properly secured in an appropriate child passenger restraint system in a rear seat, not simply in a restraint anywhere in the vehicle. Section 27363 sets the narrow exceptions, including a vehicle with no rear seat and rear seats already occupied by children 7 or under.

A child under 8 who has reached 4 feet 9 inches may be secured by the vehicle safety belt instead of a child restraint system. A child 8 or older may use the safety belt as well.

Even when a booster is no longer required, parents should confirm the lap belt sits low across the thighs and the shoulder belt crosses the center of the chest. That fit check becomes the legal standard for children ages 8 through 15 on January 1, 2027.

What Is Changing Under AB 435?

Beginning January 1, 2027, California’s child passenger safety laws will change under Assembly Bill 435 (AB 435). The new law is designed to place greater emphasis on whether a vehicle’s seat belt fits a child properly, rather than relying primarily on age or height when determining if a booster seat is still needed.

Under AB 435, the phrase “properly restrained by a safety belt” takes on a new statutory definition built around a five-step fit test. The amended Vehicle Code Section 27360.5 applies that standard to children ages 8 through 15, so a child who may legally use a safety belt today could need to stay in a booster seat if the belt does not fit. The test evaluates whether:

• The child can sit with their back completely flat against the vehicle’s seatback.
• Their knees naturally bend over the front edge of the auto seat cushion.
• The shoulder strap crosses snugly over the middle of the chest and collarbone, without riding up onto the neck.
• The lap belt stays low and tight across the upper thighs or hips, never riding up onto the stomach.
• The child can stay seated that way for the whole trip.

The goal is to move a child out of a booster seat only when an adult seat belt actually fits. Until then, today’s California car seat laws still control.

What Happens if Car Seat Laws Are Violated?

Violating CA car seat laws can result in traffic citations and fines, but the consequences may extend beyond a financial penalty if a child is injured in a crash. Properly securing a child is both a legal requirement and an important safety measure designed to reduce the risk of serious injuries.

If law enforcement determines that a child was not properly restrained, the driver may receive a citation under Vehicle Code Section 27360. The base fine is $100 for a first violation and $250 for each later violation, and the amount actually owed runs higher once court fees and penalty assessments are added. A conviction also adds one point to the driver’s record, which can affect insurance rates.

A restraint violation does not automatically determine who is responsible for a collision. If another driver caused the crash through negligent behavior, liability is still evaluated based on the available evidence. The way a child was restrained, however, may become one factor considered during an insurance claim or personal injury lawsuit.

How Do California Car Seat Laws Affect Car Accident Claims?

California car seat laws affect a car accident claim in one specific way: they give the insurer an argument about how much a family recovers, not about whether the other driver caused the crash. Investigators will look at whether the child was restrained correctly and whether the restraint system was installed to the manufacturer’s instructions. The driver who caused the collision remains responsible for causing it.

What Insurers Review After a Crash Involving a Child

Insurance companies frequently review police reports, photographs, witness statements, and medical records after a car accident involving a child. They may also examine the condition of the child restraint system and whether it was installed according to the manufacturer’s instructions.

How Pure Comparative Fault Works in California

California follows pure comparative fault, which means a share of responsibility reduces a recovery rather than blocking it. If 20 percent of the fault were assigned to one party, that party’s recovery would be reduced by 20 percent, and there is no cutoff at 50 percent as some states apply.

California courts treat the failure to use an available restraint the same way. It counts as comparative negligence, which means it can lower what a family recovers but does not end the claim. Because every crash turns on its own facts, a restraint question alone rarely decides an insurance claim or lawsuit.

Commercial Vehicle Accidents Involving Child Passengers

When a child passenger is hurt by a delivery van, tractor-trailer, bus, or other commercial vehicle, the claim usually involves more than one insurance policy and more evidence than an ordinary crash. The commercial driver, the company that employs them, and sometimes a separate vehicle owner can each carry coverage. Call 866-864-5477 and we will tell you which records need to be preserved first.

Evidence Unique to Commercial Vehicle Claims

When a commercial vehicle is involved, investigators may review driver logs, electronic data, maintenance records, and company safety policies in addition to the evidence collected at the accident scene. These materials can help determine how the collision occurred and whether the commercial driver, employer, or another party may share responsibility.

Multiple Insurance Policies in a Commercial Crash

A commercial crash can put several layers of coverage in play at once. The driver may be covered by a company policy, the employer may carry its own liability coverage, and an excess or umbrella policy may sit above both. The same child car seat laws apply either way, but sorting out which policy responds first often decides how quickly a family sees anything.

California generally gives an injured person 2 years from the date of injury to file a personal injury lawsuit, under Code of Civil Procedure Section 335.1. Two things change that math. A claim against a public entity, such as a transit bus, runs on a much shorter government claim deadline, and a child’s own claim is treated differently from a parent’s.

What Should Parents Do After a Crash Involving a Child?

A crash involving a child can be frightening, even when injuries are not immediately apparent. Taking a few practical steps afterward may help protect both the child’s health and any future insurance claim.

• Seek medical evaluation as soon as possible: A prompt examination creates a record that connects any injury to the crash. That documentation often matters later if an insurance claim arises.
• Replace the car seat if necessary: The National Highway Traffic Safety Administration recommends replacing many child restraint systems after a moderate or severe crash. Parents should review both the manufacturer’s guidance and federal recommendations before continuing to use the seat.
• Document the accident scene: Photographs of the vehicles, the child restraint system, road conditions, and visible damage may help preserve important evidence. Keeping copies of medical records and repair estimates may also be useful.
• Report the collision to the insurance company: Providing timely notice allows the claims process to begin while evidence is still available. Families should answer questions truthfully and keep records of all communications.

Taking these steps is helpful for families focusing on their child’s recovery while preserving information that may become important if questions about liability or insurance coverage arise later.