Tools · Car Seat
Colorado Car Seat & Booster Checker (2026)
Enter your child's age, height, and weight to see the minimum seat stage Colorado law requires and the first-offense fine (About $82). This is the legal minimum — not best safety practice.
Colorado car seat checker
4′9″ = 57 in. Enter only the boxes you have. Colorado 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.
Heads up: 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 Any summary quoting "under 1 / 20 lb" or "booster to 8" describes the repealed pre-2025 version.
- Child
- Not entered
- Minimum legal stage
- Enter age / height / weight
- 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
- First-offense fine
- About $82
Plain-language summary, not legal advice.
This shows the minimum legal requirement in Colorado, not best safety practice, which is usually stricter, and not legal or safety advice. Always follow your car seat's manufacturer instructions. For the full four-stage rules, front-seat rule, and citation, see the Colorado car seat law reference, cited to C.R.S. §42-4-236 (as amended by HB24-1055) (last reviewed 2026-07-11).
How Colorado car seat law works
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in 14 years, and older summaries quoting "rear-facing under 1 and 20 lb" or "booster to age 8" are describing the repealed version.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.
This checker shows the Colorado minimum legal requirement — not best safety practice, which is usually stricter — and is not legal or safety advice. For the full four-stage rules, front-seat rule, and citation, see the Colorado car seat law reference.
Car seat checkers for other states
Same tool, each with its own booster-exit rule.