Booster seat requirements in Wisconsin
A car seat or booster until age 8.
Unless the child is taller than 57 inches (4 ft 9 in) or weighs at least 80 lb, which ends the requirement whatever their age.
- Rear facing until
- 12 months
- Seat belt alone from
- age 8
Every figure on this page was read at Wis. Stat. § 347.48(4) on 4 October 2026. Read the statute
What the Wisconsin booster seat law says
The stages below are separate rules in the statute, not one rule in steps.
| Rule | Figure | What Wisconsin requires |
|---|---|---|
| Rear facing | under 12 months | Until 12 months (1 year). |
| Car seat or booster | under 8 years | Until age 8, unless the child is taller than 57 inches (4 ft 9 in) or weighs at least 80 lb. |
| Adult seat belt alone | from 8 years | Lawful from age 8, or once the child reaches more than 57 inches (4 ft 9 in) or 80 lb. |
| Penalty | no figure | No amount recorded. Condition A forfeiture set by the child's age. For a child under four, $30 to $75, with no forfeiture assessed if the vehicle had no suitable seat, the driver fits one within 30 days, and the driver has not been cited for this in the preceding three years. For a child of four to seven, $10 to $25 for a first offense and $25 to $200 for a second or later conviction within three years (Wis. Stat. § 347.50(3) and (4)). |
Size ends the requirement, whichever comes first. A child who is taller than 57 inches (4 ft 9 in) or weighs at least 80 lb is out of the booster in Wisconsin whatever their age. A child who has not reached that stays in one until age 8. The size is an escape from the age rule rather than a second thing that also has to be true. Wisconsin gives more than one, and meeting either is enough.
Where this and size guidance disagree, follow the stricter one. A belt that crosses the neck rather than the middle of the chest is worse protection than a booster even where the statute allows it.
The statute
Wisconsin sets this in Wis. Stat. § 347.48(4). Read it at the source.
This is information, not legal advice. A city or county in Wisconsin can set a stricter rule than the state one, and an officer enforces the text of the statute rather than a summary of it. Where this page and the statute differ, the statute is right and this page is a bug.
Where this comes from
- Statute
- Wis. Stat. § 347.48(4)
- Source
- docs.legis.wisconsin.gov
- Jurisdiction
- Wisconsin (WI), state law only
- Last reviewed
- 4 October 2026 0 days ago
- Read at the statute
- 4 October 2026
- Signed off by a person
- Not yet
- Amendment history
- Last amended by 2011 Wis. Act 111. The compilation read carries its own currency line: updated through 2025 Wis. Act 247 and in effect on 1 October 2026.