When to Switch From Infant Car Seat to a Convertible One

Mother buckling child into car seat

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Many parents wonder when their child is ready to switch from an infant car seat to a convertible or forward-facing car seat. Car seats are essential for your child's safety, so it's important to stay up-to-date on usage guidelines. However, all the recommendations can get confusing, especially as the timing on when to switch from an infant seat varies from child to child based on their age, height, and weight, as well as the recommendations for the specific car seat they are using.

According to the American Academy of Pediatrics, it's ideal for kids to stay in a backward-facing seat as long as possible, ideally until after age 2. While you may elect to use a convertible car seat from when your baby is born, most new parents choose an infant seat for their newborns. This is primarily because of the convenience infant car seats provide. However, it's worth noting both are safe options so long as you follow the manufacturer's guidelines for that particular car seat.

Let's explore the different types of car seats, how to use each option safely, and when it's time to transition to a convertible seat.

Infant and Convertible Car Seats: What's the Difference?

Parents have the option of choosing between an infant and a convertible car seat when traveling with their baby. Both are safe options if your baby meets the car seat's height and weight recommendations. You also have to make sure you know how to securely install the seat. It's important to choose the seat that works best for your baby and your needs. Here are the key differences between infant and convertible car seats.

Infant Car Seats

Infant car seats are the more popular choice for parents of new babies. These car seats attach to a base installed in your vehicle and can only be used rear-facing. Parents can easily remove infant car seats from their base with the click of a button. Infant car seats also have a handle for carrying your baby to and from the car, making it easy to transport your baby without having to remove the child from the seat.

Another benefit of infant car seats is they are often sold as part of a travel system. Travel systems generally include a car seat and stroller that are compatible. This means you can affix the infant seat to the stroller without having to take your baby out of the car seat.

While babies often fall asleep in their car seats, it's recommended that parents remove their sleeping baby from their car seat when they get home or to their destination. Never take a baby—sleeping or awake—out of the car seat when you are in the car.

When not in a car, sleeping babies should be placed alone, on their backs, in a crib bassinet or play yard that has a firm flat surface with no blankets, toys, or stuffed animals in it.

Convertible Car Seats

Unlike infant car seats, convertible car seats can be used rear-facing for the first few years of the child's life, and then forward-facing. Per the AAP recommendations, children should ride rear-facing in their convertible seat until reaching the max rear-facing height or weight limit—and only then should the convertible seat be turned forward-facing.

Then the child should use it forward-facing until reaching the max height or weight (whichever comes first) for forward-facing. It should be noted that the rear-facing limits (height and weight) are almost always lower than the forward-facing limits.

Some kids will need a seat with a higher height or weight limit than their convertible seat offered in order to remain harnessed before they are ready to transition to a booster. Most convertible seats go rear-facing to at least 40 pounds and forward-facing to at least 50 pounds. However, most kids are too tall for convertible car seats that have an upper weight limit of 40-50 pounds.

Convertible car seats are installed in the vehicle on their own without a base. This means a baby using a convertible car seat must be carried to and from the vehicle with each use.

"The convertible seat has a higher weight and height limits for rear-facing than the infant rear-facing only seats," said Eric Anderson, MD, pediatrician at Atrius Health in Burlington, Massachusetts. "This makes them perfect for larger babies and toddlers."

They also are ideal for keeping preschoolers rear-facing. Most convertible seats can take most kids rear-facing until at least age 3, and many can take kids rear-facing until 4 to 5 years of age if not more.

These car seats tend to be larger than infant car seats, so you may wonder how your little one could fit in a convertible car seat securely. It's important to review the specifications for each seat to ensure your baby meets the minimum guidelines to travel safely in your chosen convertible car seat.

Your convertible car seat may come with inserts that can be added and removed based on your baby's size. Use these inserts as directed in the manual, and do not add any accessories to your baby's car seat that the manufacturer hasn't approved.

When Should You Make the Switch?

While infant car seats have weight limits ranging from 22 to 35 pounds, nearly every baby is too tall before reaching the weight limit, especially for the seats with 30+ pound limits. Too tall is when the child's head is 1 inch below the top of the seat. It would be best if you familiarized yourself with your car seat's height and weight requirements to ensure your child is riding safely.

The American Academy of Pediatrics (AAP) recommends transitioning your baby from the infant seat to a rear-facing convertible seat, once they meet the minimum height or weight requirement for their infant seat. If a child is over the weight limit but still within the height limit, it is not safe to use the seat (and vice versa also is not safe). Once your child reaches one limit, they are too big.

When Should You Transition From an Infant Seat to a Convertible Seat?

Your child has outgrown their infant seat if:

  • They are above the seat's limit for height – typically around 32 to 35 inches.
  • They are above the seat's limit for weight – typically 30 to 35 pounds.
  • Their head is one inch or less from the top of the seat.

While the max height for most infant seats is when the child's head is 1 inch below the top of the seat, crash testing from Consumer Reports (CR) indicates that it may be best to transition to the rear-facing convertible seat earlier, before your child's head is within an inch of the top.

CR's crash tests with a 12-month-old dummy showed that the risk of head injury is much greater in an infant seat than a rear-facing convertible seat—as the dummy hit its head on the back of the front seat in more than half of the crashes in infant seats, but in only 4% of the crashes when in a convertible seat.

Rear-facing kids will slide up their car seat. A child in a convertible seat has a lot more of the car seats's shell above their head, making it much less likely that the child's head will slide over the shell of the car seat and be able to hit something hard, like the back of the front seat.

Important Safety Considerations

Switching to a convertible car seat is a major transition that parents should not take lightly. When selecting and installing your new car seat, it's important to keep certain safety considerations in mind to protect your child in the event of a crash.

Install the Seat Correctly

The car seat should be installed using either the seatbelt or LATCH system—not both. Be sure to refer to the manual when installing your child's car seat. Note that a correctly installed car seat should not move more than one inch side-to-side or front-to-back.

Know Your State Laws

Some states require children to ride rear-facing in their car seats until age two, although many states allow you to turn your child forward-facing at a year legally. Children are safer riding rear-facing than forward-facing.

Rear-facing kids suffer fewer injuries to all parts of the body, including the head, neck, and legs. This is why the AAP recommends that children remain rear-facing in their convertible seat as long as possible—until reaching the max height or weight for their convertible seat—which for many kids is between 3 to 5 years of age.

Harness Your Child Correctly

Car seat straps should be at or below your child's shoulders when rear-facing and at or above your child's shoulders if forward-facing. Straps should lie flat and be free of any twisting. Once buckled, you should adjust the harness until the straps are snug. It is literally impossible to make the straps "too tight" on almost every car seat—even if you are an NFL linebacker.

Because nearly every child is riding in straps that are too loose, the focus needs to be on getting them properly snug and not worrying about making it too tight. This is a harness the child's life depends on. You don't want to assume your child is buckled in correctly. Check for proper fit every time you buckle the child. The pinch test misses the fact that there is often oodles of slack hidden in the straps at the hip and belly area. Finally, position the chest clip at armpit level.

A Word From Verywell

Most parents begin with an infant car seat and later transition their child to a convertible. It's important to choose a car seat that works best for you and your child. A safe car seat is one that has not been in an accident and can be securely installed in your vehicle.

Keeping your child rear-facing until at least age 2 is the safest option for preventing injuries and fatalities in the event of a crash. Be sure your child's car seat is installed and harnessed as outlined in its manual. If you have questions about your child's car seat, don't hesitate to reach out to the company directly for more information.

1 Source
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  1. Consumer Reports. When It's Time to Upgrade Your Child's Car Seat.

By Renee Plant
Renee Plant is a health and wellness freelance writer with a passion for delivering well-researched, factual content to readers.