Car seat laws in Wisconsin specify the age and weight your children must be at in order to use certain types of car seats. Other regulations, such as booster seat laws, indicate how old your child must be before he or she can ride without using a safety seat anymore. Given that car accidents are a leading cause of injury among children younger than 13 years of age, it is important that you learn how to properly use car seats and how to choose the correct type of seat for your child.


If you fail to follow regulations, such as those for the correct booster seat age, then you can receive a fine as well as a traffic ticket. Failing to use the correct type of seat not only leads to tickets, but it is also unsafe for your children. Below, learn more about car seat safety in Wisconsin and discover which rules you need to follow as your children grow.

What are the car seat laws in Wisconsin?

Laws determine the correct car seat ages as well as weights for different types of safety harnesses. In general, the child car seat laws in Wisconsin state that all children younger than eight years of age or shorter than four feet and nine inches in height must ride in a safety seat that is appropriate for their size. However, there are also specific regulations for each age group and size, including the following:

  • Babies younger than one year old or infants that weigh less than 20 pounds must ride in a rear-facing seat.
  • Children who are at least one year of age and weigh more than 20 pounds must ride in a forward- or rear-facing seat until they reach four years of age or weigh at least 40 pounds.
  • When a child is between four and eight years of age or when he or she weighs between 40 and 80 pounds, the child must ride in a size-appropriate car seat or booster seat.
  • Once a child turns eight years of age or reaches four feet and nine inches in height, he or she can ride with either a booster seat or an adult seat belt if the straps fit safely.

Note that the car seat requirements in Wisconsin allow you to choose between a booster seat, forward-facing seat or rear-facing seat when your child is in certain age or weight brackets. Because some specifications, such as the booster seat weight requirements, vary by manufacturer, it is your responsibility to choose the correct type of safety harness for your child based on his or her size.

The recommended car seat weight will generally be the same when looking at seats that use the same design, but you should always check each individual brand before making any assumptions.

Penalties for Violating Car Seat Regulations in Wisconsin

The consequences for not meeting a car seat requirement in Wisconsin vary based on the number of times you have violated the law as well as your child’s age. In general, the penalties are more severe if you have broken the law more than once or if your child is younger. The consequences of failing to use a car seat correctly include the following:

  • A fine of $175.30 if your child is younger than four years of age
  • If your child is between four and eight years of age:
    • A $150.10 fine for your first offense
    • A $200.50 fine for your second offense
    • A $263.50 fine for each subsequent offense

When it comes to child car seat safety, you will not be exempt from the law if you remove your child from his or her seat to handle personal needs (such as a diaper change) when the car is moving. In order to avoid paying a fine in Wisconsin, the vehicle must be stopped in a safe location before you can remove your child from his or her safety seat.

Types of Car Seats

To meet the car seat requirements in Wisconsin, you can choose between several different types of seats. While these seats comply with the law, you still need to ensure you meet the recommended booster seat weight or other requirements for each seat.

Remember, even for similar designs, the exact car seat weight can vary based on which brand of seat you purchase. Contact one of the local DMV offices in Wisconsin if you have questions. The standard types of seats you can buy include:

  • A rear facing car seat, which is intended for infants and babies younger than one year of age who weigh up to 20 pounds. Rear-facing seats can be used up to a child’s third birthday, provided that he or she meets the manufacturer’s weight requirements.
  • A forward facing car seat, which can be used for children who weigh between 20 and 40 pounds. Children are usually between one and four years of age at these weights.
  • A booster seat, which can be used as early as four years of age, provided your child weighs at least 40 pounds. The recommended booster car seat age may vary by brand or manufacturer, but remember that the laws state your child must use a booster until he or she is eight years of age or reaches the height requirement.

In addition to these standard designs, there are several variations. For example, some of the best car seats are convertible or all-in-one styles, which transform from a rear-facing to a forward-facing seat when your child is ready. All-in-one designs even change into a booster seat once your child reaches the correct weight.

When looking at any style, keep in mind that the safest car seats are those that provide the maximum amount of support for your child’s head and neck. The safest seat for you may depend on the type of vehicle you drive as well. For example, you may wish to buy a high-back booster seat rather than a backless design if your vehicle does not have headrests.

Car Seat Installation Information

When installing a car seat, always refer to the seat manufacturer’s instructions as well as your vehicle owner’s manual to learn the correct steps to take. Car seats can vary slightly in their designs, which means that the instructions can be different even for similar seats from different brands.

After you install a car seat, it is a good idea to have it inspected. A variety of car seat check events are held throughout the state, and some locations will even offer inspections by appointment. Places that typically offer inspections include:

  • Medical centers.
  • Fire stations.
  • Police departments.
  • Community centers.
  • County health departments.
Last updated on Wednesday, September 23 2020.