Car seat & booster law

Missouri

Q: Is the Missouri car seat law changing?

No. As of October 6, 2026, when SeatChecker last checked the statute, no enacted change to the Missouri car seat law is scheduled. Current law: Children under 4, or under 40 pounds, must be in a car seat. Children 4 to 7 who weigh 40 to 79 pounds and are less than 4 feet 9 inches tall must be in a car seat or booster. A child who weighs at least 80 pounds or is more than 4 feet 9 inches tall may use a seat belt.

Q: What age can a child sit in the front seat in Missouri?

Missouri law sets no minimum age for riding in the front seat. A child who would otherwise need a booster may use a lap belt only in the back seat if that position has no combination lap and shoulder belt. The child restraint rules still apply: a car seat or booster is required until age 8 or 4'9". The American Academy of Pediatrics recommends the back seat for all children under 13. That is best practice, not a legal requirement in Missouri.

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

Once the child weighs at least 80 pounds or is more than 4 feet 9 inches tall (children 8 and older are not covered by the booster requirement). Pediatricians recommend a booster until the seat belt fits properly.

Q: Does Missouri require children to ride rear-facing, and until what age?

No. Missouri law does not set a rear-facing age. The law only requires that a child under 4 years old, or under 40 pounds, ride in a child passenger restraint. Pediatricians still recommend keeping a child rear-facing as long as the car seat allows, but that is a safety recommendation and not a legal requirement in Missouri.

Q: What is the fine for a car seat violation in Missouri?

A violation is an infraction punishable by a fine of not more than $50, plus court costs.

Verified · OCT 2026

Quick answer · Missouri

A car seat or booster is required until your child is 8 years old or taller than 4'9".

Children under 4, or under 40 pounds, must be in a car seat. Children 4 to 7 who weigh 40 to 79 pounds and are less than 4 feet 9 inches tall must be in a car seat or booster. A child who weighs at least 80 pounds or is more than 4 feet 9 inches tall may use a seat belt.

Rear-facing per seat Forward per seat Booster < 8 yr Belt 8+ yr

Mo. Rev. Stat. § 307.179 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: Not specified by law
Booster until: Age 8 or 4'9"
Front seat: No age set in law

Pediatricians recommend

AAP: safer, not the law

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

AAP guidance is a safety best practice and is separate from Missouri's legal minimum, which uses an 80-pound weight cutoff. Pediatricians recommend a booster until the seat belt actually fits.

Every stage, by the law

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

Missouri car seat law requirements by restraint stage, age, height, weight, and statutory citation.
Stage	Age	Height	Weight	Citation
Rear-facing	Infant (per seat)	—	—	Guidance
Forward-facing	Toddler (per seat)	—	—	Guidance
Booster	until 8 yr	≤ 4'9" / 145 cm	< 80 lb / 36 kg	Mo. Rev. Stat. § 307.179
Seat belt	8 yr +	or > 4'9" / 145 cm	or ≥ 80 lb / 36 kg	Mo. Rev. Stat. § 307.179
Back seat / front seat	Recommended < 13	—	—	Guidance

Rear-facing Guidance

Age: Infant (per seat)

Forward-facing Guidance

Age: Toddler (per seat)

Booster Mo. Rev. Stat. § 307.179

Age: until 8 yr
Height: ≤ 4'9" / 145 cm
Weight: < 80 lb / 36 kg

Seat belt Mo. Rev. Stat. § 307.179

Age: 8 yr +
Height: or > 4'9" / 145 cm
Weight: or ≥ 80 lb / 36 kg

Back seat / front seat Guidance

Age: Recommended < 13

Frequently asked questions

What is the car seat law in Missouri in 2026?

Is the Missouri car seat law changing?

No. As of October 6, 2026, when SeatChecker last checked the statute, no enacted change to the Missouri car seat law is scheduled. Current law: Children under 4, or under 40 pounds, must be in a car seat. Children 4 to 7 who weigh 40 to 79 pounds and are less than 4 feet 9 inches tall must be in a car seat or booster. A child who weighs at least 80 pounds or is more than 4 feet 9 inches tall may use a seat belt.

What age can a child sit in the front seat in Missouri?

Missouri law sets no minimum age for riding in the front seat. A child who would otherwise need a booster may use a lap belt only in the back seat if that position has no combination lap and shoulder belt. The child restraint rules still apply: a car seat or booster is required until age 8 or 4'9". The American Academy of Pediatrics recommends the back seat for all children under 13. That is best practice, not a legal requirement in Missouri.

When can my child stop using a booster in Missouri?

Once the child weighs at least 80 pounds or is more than 4 feet 9 inches tall (children 8 and older are not covered by the booster requirement). Pediatricians recommend a booster until the seat belt fits properly.

Does Missouri require children to ride rear-facing, and until what age?

No. Missouri law does not set a rear-facing age. The law only requires that a child under 4 years old, or under 40 pounds, ride in a child passenger restraint. Pediatricians still recommend keeping a child rear-facing as long as the car seat allows, but that is a safety recommendation and not a legal requirement in Missouri.

What is the fine for a car seat violation in Missouri?

A violation is an infraction punishable by a fine of not more than $50, plus court costs.

Sources

Verified · OCT 2026

How Missouri compares

Where Missouri ranks among all 50 states, DC, and the US territories on each measure. Rankings compare legal minimums only and are not safety ratings.

Strictest car seat laws by state
#29 of 56, tied · 42 / 100
Rear-facing car seat laws by state
No statutory age, not ranked
Booster seat laws by state
#10 of 52, tied · Age 8
Car seat fines by state
#11 of 28, tied · $50
Back seat laws by state
No back-seat law, not ranked

See all car seat law rankings →

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