On January 1, 2025, Colorado’s child passenger law changed in a way that still surprises parents on the Front Range. House Bill 24-1055 amended Colorado Revised Statutes 42-4-236 and raised the age at which a child must ride in a child restraint system. The prior cutoff was the eighth birthday. The new cutoff is the ninth.

The General Assembly stated the reason in the signed act. From 2015 to 2019, 48 children under age eight were killed in Colorado passenger-vehicle crashes. The same legislative declaration attributes to the Colorado Department of Transportation an estimate that 59 percent to nearly 84 percent of children ride improperly restrained. Those figures are the legislature’s own stated basis for rewriting the age bands.

What 42-4-236 now requires

Under the amended 42-4-236(2)(a)(I), every child under nine years of age who is being transported in this state in a motor vehicle, or in a vehicle operated by a child care center, must be properly restrained in a child restraint system according to the manufacturer’s instructions, unless an exemption in subsection (3) applies. That is a full year later than the rule many booster-seat boxes and older driving guides still describe. A child who turned eight in December 2024 did not age out of the restraint requirement on New Year’s Day.

What if a crash still happens?

Families sometimes speak with personal injury lawyers Colorado Springs or another injury firm when a crash on I-25 or a Colorado Springs arterial raises both restraint questions and questions about another driver’s conduct. The statute supplies the ages and weights. It does not decide fault. Once a child reaches age nine, 42-4-236(2)(b) requires a safety belt or a child restraint, according to the manufacturer’s instructions, through the child’s eighteenth birthday. The seat-belt band used to end at sixteen, so the 2025 amendment also lengthened that second band by two years.

The age bands below nine are more specific. Section 42-4-236(2)(a)(II) provides that a child under two years of age must ride in a rear seat if a rear seat is available, in a rear-facing restraint if the child weighs under 40 pounds, and in a rear-facing or forward-facing restraint if the child weighs 40 pounds or more. Section 42-4-236(2)(a)(III) requires a child who is at least two and under four to use a rear-facing or forward-facing restraint and, if a rear seat is available, to ride in that rear seat. Section 42-4-236(2)(a)(IV) then covers children who are at least four and under nine and who weigh at least 40 pounds: those children must use a child restraint system or booster seat and, if a rear seat is available, must ride in the rear seat.

A gap the statute leaves open

Colorado’s legal minimum is not the same as the federal safety recommendation. The National Highway Traffic Safety Administration advises keeping a child rear-facing until the child reaches the height or weight limit set by the seat’s manufacturer, and keeping children in the back seat at least through age 12. Those recommendations last longer than the ages written into 42-4-236.

The same NHTSA page reports that 39 percent of children killed in car crashes in 2024 were unrestrained, and that car seats saved 325 children under age five in one year. The statute’s job is to set a floor. The agency’s figures explain why traffic-safety guidance still tells parents to stay in each stage until the seat’s own limits, not merely until the ninth birthday. After January 1, 2025, treating the eighth birthday as the end of the booster years is a reading of a statute that is no longer in force. The host’s guide to how long kids need to be in car seats walks through those longer federal and pediatric recommendations, which last past Colorado’s ninth-birthday legal floor.