Car seat laws vary more than most parents expect, and Missouri is no exception. Below are the current Missouri requirements for rear-facing seats, forward-facing seats, boosters, and seat belts, verified against the official Missouri Revisor of Statutes.
Law data last verified against official state sources: October 4, 2026.
Quick answer
Missouri requires a child passenger restraint for children under 4 or under 40 lbs, a restraint or booster for ages 4–8 (40–80 lbs, under 4’9″), and belts at 80+ lbs or over 4’9″. No general front-seat age ban.
Missouri car seat requirements by age and size
| Stage | What Missouri law requires |
|---|---|
| Rear-facing | Not specified on official source — the statute requires children less than 4 years of age (regardless of weight) and children weighing less than 40 pounds (regardless of age) to be secured in an appropriate child passenger restraint system. |
| Forward-facing | Not specified on official source. |
| Booster seat | Children at least 4 but less than 8 years of age, weighing at least 40 but less than 80 pounds, and less than 4’9″ tall: secured in a child passenger restraint system or booster seat appropriate for the child. |
| Seat belt only | Children weighing at least 80 pounds or more than 4’9″ tall: secured by a vehicle safety belt (or appropriate booster seat). |
Fines and penalties in Missouri
Fine: not published on the official state source. Note: .
Front seat rules in Missouri
Front-seat rule: No general front-seat age ban — the statute provides that when there are more children than seating positions, unrestrained children sit behind the front seat (unless the vehicle is front-seat only).
The official law
- Statute: RSMo § 307.179
- Official source: Missouri Revisor of Statutes
Missouri car seat law FAQs
What is the fine for a car seat violation in Missouri?
Fine: not published on the official state source. Note: .
When can my child stop using a booster seat in Missouri?
Children at least 4 but less than 8 years of age, weighing at least 40 but less than 80 pounds, and less than 4’9″ tall: secured in a child passenger restraint system or booster seat appropriate for the child. Children weighing at least 80 pounds or more than 4’9″ tall: secured by a vehicle safety belt (or appropriate booster seat).
Does Missouri law require rear-facing car seats?
Not specified on official source — the statute requires children less than 4 years of age (regardless of weight) and children weighing less than 40 pounds (regardless of age) to be secured in an appropriate child passenger restraint system.
Can my child ride in the front seat in Missouri?
Front-seat rule: No general front-seat age ban — the statute provides that when there are more children than seating positions, unrestrained children sit behind the front seat (unless the vehicle is front-seat only).
Where can I read the official Missouri car seat law?
Statute: RSMo § 307.179 Official source: Missouri Revisor of Statutes.
Check another state
Driving across state lines? Requirements change at the border — use our interactive car seat law checker to look up any state by your child’s age, weight, and height.
Related state guides:
This page is for general informational purposes only and is not legal advice. Child passenger safety laws change — always verify current requirements with your state’s DMV, highway safety office, or the official statute linked below before making decisions.