Missouri Car Seat Laws
Missouri car seat laws: rear-facing, forward-facing, booster, and seat belt rules for kids by age and weight.
Missouri child car seat law requires the following, by age and size. Verify the current statute before traveling.
| Stage | Min age | Min weight | Min height | Note |
|---|---|---|---|---|
| Rear-facing | Age 1+ | 20 lbs | — | |
| Forward-facing | Age 4+ | 40 lbs | — | |
| Booster seat | Age 8+ | — | 57” tall | |
| Seat belt | Age 8+ | — | 57” tall |
Front seat rules
Not specified — the law does not set a minimum front-seat age. Safety groups recommend keeping children in the back seat until 13.
Penalties
A violation can cost $50. Officers can pull you over for a child restraint violation (primary enforcement in most states).
Statute
Source: Mo. Rev. Stat. § 307.179. Last verified: 2026. Car seat laws change — check your state DMV or highway patrol before a long trip.
Frequently Asked Questions
How long must a child stay rear-facing in Missouri?
Until at least age 1 or 20 lbs, whichever comes first. Many experts recommend rear-facing longer than the legal minimum.
When can a child use a booster seat in Missouri?
After outgrowing the forward-facing harness — generally around age 4 or 40 lbs — until age 8 or 57” tall.
What is the fine for a car seat violation in Missouri?
About $50, plus possible court costs. Fines vary by county and repeat offenses may be higher.