Car seat & booster law

Washington

Q: When can my child stop using a booster in Washington?

When the child reaches 4 feet 9 inches and the seat belt fits properly. Washington's booster requirement is based on height, not a set age.

Q: Does Washington require rear-facing car seats, and until what age?

Yes. In Washington a child under 2 must ride rear-facing, and a child under 4 must be in a forward-facing seat with a harness. Pediatricians recommend keeping a child rear-facing as long as the seat allows.

Q: Do children have to ride in the back seat in Washington?

Yes. Washington requires children under 13 to ride in the back seat where it is practical to do so. The American Academy of Pediatrics also recommends the back seat as the safest place for every child under 13.

Verified · JUN 2026

Quick answer · Washington

A car seat or booster is required until your child is taller than 4'9".

Children under 2 must ride rear-facing. Children under 4 must be in a forward-facing seat with a harness. Children under 4 feet 9 inches must be in a booster. Children under 13 must ride in the back seat where practical.

Rear-facing < 2 yr Forward 2+ yr Booster Belt

RCW 46.61.687 Read the statute

Car seat law checker

The legally required restraint, by state.

General information, not legal advice.

SeatChecker

Required vs recommended

What the law enforces, and what pediatricians advise. They are not the same.

The law requires

Minimum, or it's enforceable

Rear-facing until: Age 2
Booster until: 4'9"
Back seat: Required under 13

Pediatricians recommend

AAP — safer, not the law

Rear-facing until: To seat limit (often age 2+)
Booster until: 4'9" — typically age 8–12
Back seat: Until age 13

AAP guidance is a safety best practice and is separate from Washington's legal minimum. Washington's law already tracks the recommendations closely, including back seat use through age 13.

Every stage, by the law

Dual units shown throughout (in + cm, lb + kg). Rows marked Guidance are best practice, not a statutory requirement in Washington.

Washington car seat law requirements by restraint stage, age, height, weight, and statutory citation.
Stage	Age	Height	Weight	Citation
Rear-facing	Birth – 2 yr	—	—	RCW 46.61.687
Forward-facing	2 yr – 8 yr	—	—	RCW 46.61.687
Booster	—	< 4'9" / 145 cm	—	Guidance
Seat belt	—	or ≥ 4'9" / 145 cm	—	Guidance
Back seat	under 13 yr	—	—	RCW 46.61.687

Rear-facing RCW 46.61.687

Age: Birth – 2 yr

Forward-facing RCW 46.61.687

Age: 2 yr – 8 yr

Booster Guidance

Age: —
Height: < 4'9" / 145 cm

Seat belt Guidance

Age: —
Height: or ≥ 4'9" / 145 cm

Back seat RCW 46.61.687

Age: under 13 yr

Frequently asked questions

What is the car seat law in Washington in 2026?

Children under 2 must ride rear-facing. Children under 4 must be in a forward-facing seat with a harness. Children under 4 feet 9 inches must be in a booster, and children under 13 must ride in the back seat where practical.

When can my child stop using a booster in Washington?

When the child reaches 4 feet 9 inches and the seat belt fits properly. Washington's booster requirement is based on height, not a set age.

Does Washington require rear-facing car seats, and until what age?

Yes. In Washington a child under 2 must ride rear-facing, and a child under 4 must be in a forward-facing seat with a harness. Pediatricians recommend keeping a child rear-facing as long as the seat allows.

Do children have to ride in the back seat in Washington?

Yes. Washington requires children under 13 to ride in the back seat where it is practical to do so. The American Academy of Pediatrics also recommends the back seat as the safest place for every child under 13.

Sources

Verified · JUN 2026

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