Colorado Car Seat Laws (2026): Ages, Rear Seat & the Rear-Seat Change

Colorado runs an age-and-weight-staged restraint law under C.R.S. § 42-4-236, with a 2024 change (HB 24-1055), effective January 1, 2025, now requiring a rear-seat placement, where one is available, for every stage from under 2 through age 8. This page reflects the statute's text as of September 2026.

Jurisdiction scope: This article covers car seat and child-restraint law in the state of Colorado only. It does not address any other state. For other states, see the car seat laws hub.

Under 2: rear seat if available, weight-gated orientation

Section 42-4-236(2)(a)(II) requires that a child under 2 "be properly restrained in a rear seat of the vehicle, if a rear seat is available," and then splits by weight: "in a rear-facing child restraint system if the child weighs under forty pounds; or...in a rear-facing or forward-facing child restraint system if the child weighs forty pounds or more." A child under 2 who has reached 40 pounds may legally use a forward-facing restraint under Colorado's statute, even though many manufacturers and safety advocates recommend staying rear-facing longer.

Age 2 through 3: restraint plus rear seat

For a child "two years of age or older, but less than four years of age, and weighs at least twenty pounds," § 42-4-236(2)(a)(III) requires a "rear-facing or forward-facing child restraint system" and, separately, placement "in the rear seat of a vehicle, if a rear seat is available."

Age 4 through 8: restraint or booster, plus rear seat

Section 42-4-236(2)(a)(IV) covers a child "four years of age or older, but less than nine years of age, and weighs at least forty pounds," requiring "a child restraint system or booster seat" and, again, "the rear seat of a vehicle, if a rear seat is available." Colorado's statute doesn't use the word "harness" anywhere in this tier; a claim that every child under 40 pounds needs a harnessed seat regardless of age has no basis in the statute's text. For a child age 4 through 8 who weighs less than 40 pounds, none of the weight-gated tiers above technically applies by its own terms, so only the general duty in (2)(a)(I), to use a restraint system "according to the manufacturer's instructions," governs; any harnessed-seat outcome in that situation follows from the seat manufacturer's own weight minimums, not from a separate statutory harness mandate.

The 2024 change, effective 2025: a new back-seat mandate for most tiers

House Bill 24-1055 is a 2024 act, effective January 1, 2025: the statute's own source note reads "L. 2024: (2)(a), (2)(b), (3)(b), and (4) amended, (HB 24-1055), ch. 376, p. 2549, section 2, effective January 1, 2025." It added the "in the rear seat of a vehicle, if a rear seat is available" language to the under-2, 2-through-3, and 4-through-8 tiers. The under-2 tier is not a case of rear-seat language appearing from nothing, though: it already required a rear seat for a child under 1 weighing under 20 pounds before the act, and HB 24-1055 widened that band to under 2 while making placement conditional on a rear seat being available. The genuinely new rear-seat mandate, with no prior form at all, is in the 2-through-3 and 4-through-8 tiers.

Age 9 through 17: belt or restraint per manufacturer instructions

Section 42-4-236(2)(b) requires that "every child who is at least nine years of age but less than eighteen years of age...shall be properly restrained in a safety belt or child restraint system according to the manufacturer's instructions."

Exemptions

Section 42-4-236(3) lists several exceptions to the restraint requirements, including a child under 9 being transported because of a medical or other life-threatening emergency when no restraint system is available; a child riding in a commercial motor vehicle operated by a child care center; a child who is themselves the driver of the vehicle, who is instead subject to the general seat belt law at § 42-4-237; and a child being transported for compensation or hire by a common carrier, contract carrier, or luxury limousine service.

Penalty

A violation is a class B traffic infraction under § 42-4-236(7)(a); a minor driver under 18 who violates the section is instead punished under § 42-2-105.5(5)(b). Subsection (8) allows the fine to be waived "if the defendant presents the court with satisfactory evidence of proof of acquisition, purchase, or rental of a child restraint system." The section itself confirms the infraction classification but does not state a dollar amount; the actual fine comes from the separate fee-schedule statute, § 42-4-1701(4)(a)(I), which sets a $65 fine plus a $16 surcharge, for an $81 total, specifically for a violation of § 42-4-236. Section 42-4-236's own cross-reference note points at that schedule. That same schedule confirms no license points attach, since § 42-4-1701(3)(c) bars the department from assessing points for a class B traffic infraction.

Federal guidance vs. Colorado law

The federal standard for car seats as products, FMVSS 213 (49 CFR 571.213), governs what a manufacturer may sell, not how a Colorado parent must use the seat. The National Highway Traffic Safety Administration and the American Academy of Pediatrics separately recommend keeping a child rear-facing as long as the seat's own height and weight limits allow, which can extend past the age and weight points where Colorado's statute first permits a switch to forward-facing. That recommendation is safety guidance, not a legal requirement layered on top of § 42-4-236.

Disclaimer: This article provides general legal information about Colorado's car seat law as of September 2026. It is not legal advice. Statutes, exemptions, and penalties change; verify the current text of the law before relying on it, and talk to a lawyer licensed in Colorado about a specific situation.

Related Colorado traffic law pages

• Colorado DUI laws
• Colorado window tint laws
• Car seat laws in every state

Statutes cited reflect their in-force version as of 2026-09-17. Last updated: 2026-09-17.

Frequently Asked Questions

Does Colorado require a rear-facing car seat under age 2?

Yes, if the child weighs under 40 pounds. Once a child under 2 reaches 40 pounds, § 42-4-236(2)(a)(II) allows either a rear-facing or forward-facing restraint, and a rear seat is required when one is available.

Did Colorado's car seat law change recently?

Yes. HB 24-1055, a 2024 act effective January 1, 2025, added a rear-seat-if-available requirement across the under-2, 2-through-3, and 4-through-8 age tiers. The under-2 tier already had a narrower rear-seat rule (under 1, under 20 pounds); the genuinely new mandate is in the 2-through-3 and 4-through-8 tiers.

What is the fine for a car seat violation in Colorado?

It's a class B traffic infraction under § 42-4-236(7)(a), carrying a $65 fine plus a $16 surcharge ($81 total) under § 42-4-1701(4)(a)(I). No license points attach to a class B traffic infraction. The fine can be waived with proof of acquiring, purchasing, or renting a conforming seat.

When can a child in Colorado stop using a booster seat?

The restraint-or-booster requirement in § 42-4-236(2)(a)(IV) runs through age 8 for a child weighing at least 40 pounds. At 9, the child moves to the belt-or-restraint-per-manufacturer-instructions tier in (2)(b).