Traffic Safety · Car Seat & Booster
Car Seat & Booster Laws in Colorado
When your child can move from a booster to a seat belt in Colorado, plus rear-facing, front-seat, and the fine, with the law kept separate from best practice.
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Check your child's stage in Colorado
Enter age, height, and weight. We show the Colorado law separately from best practice.
4′9″ = 57 in. Enter only the boxes you have; this state uses booster required from age 4 (once 40 lb or more) until the 9th birthday; Colorado uses age, not a 4′9″ height line, so a shorter child still exits the booster mandate at 9.
Educational guide to the minimum legal requirement, not legal or safety advice. Best practice is often stricter than the law. Always follow your car seat’s manufacturer instructions, and confirm the current rule with the official source below (last reviewed 2026-07-11).
The four stages in Colorado
Each rung is tagged Law or best practice.
A child under 2 who weighs less than 40 lb must ride rear-facing in a rear seat. This is codified by age and weight, so rear-facing is law in Colorado, not just a recommendation.
A child age 2 or 3 (weighing at least 20 lb), or a child under 2 who already weighs 40 lb or more, may ride in a rear-facing or forward-facing child restraint. The statute allows the switch by age and weight.
A child age 4 to under 9 who weighs at least 40 lb must use a child restraint or booster seat in the rear seat. The requirement exits at age 9; Colorado sets no height line for the booster.
Exit rule: booster required from age 4 (once 40 lb or more) until the 9th birthday; Colorado uses age, not a 4′9″ height line, so a shorter child still exits the booster mandate at 9. The adult belt must fit — lap low across the hips, shoulder belt across the chest.
Front seat, the fine & the source
Seating rule, the exact booster logic, and any recent change.
A child under 9 must ride in the rear seat if one is available. HB24-1055 made this an enforceable requirement effective January 1, 2025, not just a recommendation.
| Booster exit logic | Age only — no statutory height/weight |
| Seat belt OK | At age 9, with a properly fitting seat belt |
| First-offense fine | About $82 A violation is a class B traffic infraction. The statute does not print a dollar figure; the roughly $82 total (base fine plus surcharges) comes from Colorado’s penalty schedule. The fine may be waived with proof that a child restraint was bought or rented. |
| Statute | C.R.S. §42-4-236 (as amended by HB24-1055) |
Colorado’s law changed on January 1, 2025 (HB24-1055), the first update in 14 years. It raised rear-facing from "under 1 and 20 lb" to "under 2 and 40 lb," extended the booster requirement from under 8 to under 9, and made the rear-seat rule for under-9 enforceable. Any summary quoting "under 1 / 20 lb" or "booster to 8" describes the repealed pre-2025 version.
What Colorado parents get wrong
Colorado rewrote its child restraint law on January 1, 2025 through HB24-1055, its first change in 14 years, and older summaries quoting "rear-facing under 1 and 20 lb" or "booster to age 8" are describing the repealed version. The current law legislates rear-facing for a child under 2 who weighs under 40 lb, so orientation is real law here rather than best practice. The booster exit is age-based: a child age 4 to under 9 who weighs at least 40 lb needs a booster or restraint, and the mandate ends at the 9th birthday. Colorado does not use a 4′9″ height line, so a short 9-year-old still exits the requirement by age. The back-seat rule for children under 9 is now enforceable, not a suggestion. The statute itself sets no dollar fine; the roughly $82 figure comes from the penalty schedule.
Common questions
When can a child stop using a booster in Colorado?
At age 9. Colorado requires a booster or child restraint for a child age 4 to under 9 who weighs at least 40 lb, and it uses age rather than a 4′9″ height line, so a shorter child still exits the requirement at 9.
Does Colorado require rear-facing car seats by age?
Yes. Since January 1, 2025, a child under 2 who weighs less than 40 lb must ride rear-facing in a rear seat. That is law, not just a recommendation.
Do children have to ride in the back seat in Colorado?
Yes, for children under 9. HB24-1055 made the rear-seat rule enforceable as of January 1, 2025 when a rear seat is available.
What is the fine for a car-seat violation in Colorado?
A violation is a class B traffic infraction, roughly $82 with surcharges. The statute prints no set dollar amount, and the fine can be waived with proof that a child restraint was purchased or rented.
Not legal advicePlainStatute provides plain-language summaries of public law for general information only. This is not legal advice. Statutes change; always confirm current requirements with the official source linked above before acting.