Arizona Car Seat and Booster Law: Who Must Be Restrained Under A.R.S. § 28-907

In Arizona, every child under five must ride in a child restraint system, and children who are at least five but under eight and no taller than four feet nine inches must be in one too. That is the rule in A.R.S. § 28-907, and it applies to any driver transporting the child on Arizona highways.

The two age rules

Subsection A says a person shall not operate a motor vehicle on the highways in this state while transporting a child under five years of age unless the child is properly secured in a child restraint system.

Subsection B extends the requirement to each passenger who is at least five, under eight, and not more than four feet nine inches tall. A seven-year-old who is taller than 4'9" falls outside that requirement, and an eight-year-old does too, though the child is still subject to Arizona's general seat belt rules.

What counts as a "child restraint system"

The statute defines the term broadly: add-on, built-in, factory-installed, rear-facing, and booster seat systems all qualify, as long as they meet the federal standard in 49 CFR § 571.213. Check the seat's label for its compliance statement and follow the manufacturer's instructions for weight, height, and installation. The statute sets the legal floor for who must be restrained; it does not tell you which seat suits a particular child, and the manual for your seat does.

The penalty

A violation carries a civil penalty of $50. The statute adds that the penalty is not imposed if the person makes a sufficient showing that the vehicle has since been equipped with a child restraint system. The law is written to get seats into cars rather than to maximize fines. Penalty money goes into a child restraint fund administered by the Department of Child Safety, which the statute caps at $20,000.

Exemptions

The statute lists several exemptions, including classic vehicles, recreational vehicles, commercial drivers, medical emergencies, and situations where the number of children exceeds the available restraint space. If you think an exemption applies to your situation, read the statute text itself rather than relying on a summary.

Help getting a seat

Two provisions aim to close the access gap. Hospitals must give parents information about child restraints before discharge. And under the statute's lending program, people who cannot afford a seat may borrow one from responsible agencies such as hospitals, shelters, and clinics.

The statute also limits enforcement: a stop for this violation does not by itself justify a search of the vehicle without additional probable cause.

Why it matters after a crash

Restraint use is one of the first facts collected in any crash report. A properly restrained child is the goal; a citation is the smaller consequence. If a crash does happen, the way the child was secured can come up in insurance and injury claims, which is one more reason to get it right. Arizona's other rules about fault and distraction, such as those in Arizona's 2026 Traffic Law Changes, apply to every driver on the same trip.

Quick checklist

Under five: always in a child restraint system. Five to seven and 4'9" or shorter: still in a restraint. Seat meets federal standard 49 CFR § 571.213. Installed and used per the manufacturer's instructions. Need help? Ask the hospital or a local agency about the loaner program.

This article is general safety and legal information, not legal advice. Statute text was checked against the Arizona Legislature's published Arizona Revised Statutes.