Child safety seat laws

State law keeps children safe in vehicles

Children must be in a car seat until they reach age 4 and 40 pounds, and in a booster seat until they reach age 8, more than 80 pounds in weight, or more than 4 ft. 9 in. tall.

Tiered structure applies:

  • Less than 1 year old, or less than 20 lbs. must be in a rear-facing child seat in the back seat (if so equipped)
  • If at least one year old and 20 pounds, but less than four years old or less than 40 pounds, must be in a forward- or rear-facing child seat in the back seat (if so equipped)
  • Age 4 to age 8, and between 40-80 lbs., and no more than 4 ft. 9 in. must be in a forward- or rear-facing child seat in the back seat (if so equipped) or a booster seat

Penalty for non-compliance depends on the age of the child:

  • If less than four years of age, the total penalty is $175.30
  • If between ages 4 and 8, the total penalty is $150.10 for the first offense, $200.50 for a second offense, and $263.50 for third and subsequent offenses

There are no exemptions from these rules allowing removal of a child from a restraint to attend to personal needs (such as feeding or diapering).

Specific questions about child seats/booster seats should be directed to:

Phone: 1-855-224-3692

Email: carseatwi@childrenswi.org

Website: www.safekidswi.org

Further information and recommendations available from the National Highway Traffic Safety Administration.

Related information:

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