When kids outgrow their regular convertible car seats, they’ll start to insist that they’re way too big to be restrained like toddlers and don’t need a car seat. But here’s where you, the parent, ignore them. Kids should stay with each type of car seat as long as possible, preferably until they reach the seat’s weight limit. That’s where the harness booster seat comes into play.
The traditional booster seat is a belt-positioning booster — it uses a seatbelt to keep your child restrained — whereas a harness booster seat uses a five-point harness, like the one on infant and toddler car seats, to keep your kid in the right position. In a perfect world, kids would remain in the right upright position for the duration of the ride. But kids are kids, and they poke siblings, slouch, drop toys, and lean over to grab a bottle of water. A harness booster seat leaves much less margin for error, keeping them positioned correctly in the event of a crash.
The American Academy of Pediatrics doesn’t mince words in its guidelines: “Any child who has outgrown the rear-facing weight or height limit for her convertible seat should use a forward-facing seat with a harness for as long as possible, up to the highest weight or height allowed by her car safety seat manufacturer. It is best for children to ride in a seat with a harness as long as possible, at least to 4 years of age. If your child outgrows a seat before reaching 4 years of age, consider using a seat with a harness approved for higher weights and heights.”
And when your child does outgrow a harness-booster seat, you can make the switch, per the AAP: “Booster seats are for older children who have outgrown their forward-facing seats. All children whose weight or height exceeds the forward-facing limit for their car safety seat should use a belt-positioning booster seat until the vehicle seat belt fits properly, typically when they have reached 4 feet 9 inches in height and are 8 to 12 years of age.”
The best harness booster seats are easy to install, will last you until your child is roughly 100 pounds, and let you adjust the harness and headrest together, without the need for rethreading. Plus, they weigh less than convertible car seats, so they’re instantly more portable and easier to move between vehicles.
This car seat transitions from forward-facing harness mode to booster mode. Unlike other models, you get more use out of this one: It fits kids from 25 to 120 pounds. Britax's ClickTight technology makes for easy installation: Open, thread and buckle, and close. There's a nine-position, quick-adjust five-point harness and headrest that move together, and a two-position recline. And for hungry kids, there are four integrated cup and snack holders. This bad boy weighs 20 pounds, so while not the heaviest model on our list, it's not something you'll move around much. NHTSA ease of use rating: Not yet available.
If you're the parent who worries about leaving their kid in the car, note that this car seat is equipped with SensorSafe technology that alerts you when your child is left in the car, or if they unbuckle the chest clip while the car is in motion; you alerts show up via a vehicle receiver and an app. This seat works in rear-facing mode, forward-facing mode, and booster mode; the weight limit is 4-120 pounds. There's a three-position reclining headrest. NHTSA ease of use rating: 4 stars.
If you travel, or switch between car seats, this booster is calling your name. It weighs eight measly pounds, is suitable for kids 22-50 pounds, and turns into a backpack when not in use. It can be installed using a car’s LATCH system, or a plane seatbelt if used during flights. The frame is made from aerospace-grade aluminum. NHTSA ease of use rating: 5 stars.
Kids can use this seat from 4-120 pounds, which gets you roughly 10 years of use, and can use it longer in rear-facing mode than other comparable car seats. It goes from rear-facing harness to forward-facing harness to highback booster to backless booster seat. And the key factor here is the anti-rebound bar, which limits the rotation of the seat and thus makes the ride safer. There's an extension panel that provides five more inches of legroom for your growing kid, allowing him or her to ride longer in the recommended rear-facing mode. You can choose between 10 different headrest heights, plus there's a six-position recline. NHTSA ease of use rating: Not yet available.
This 22-pound car seat converts from a five-point harness booster, to a highback booster, and to a backless booster, and with the three different modes, fits children from 22 to 100 pounds. It installs in minutes, using either a car seat belt or LATCH. You can adjust the harness and headrest together without the need for rethreading. It has a four-position recline and integrated dual cup holder. NHTSA ease of use rating: 4 stars.
At 25 pounds, this is a hefty harness booster seat that segues into a belt-positioning booster. It's also one of the most solid ones you can buy. It seats children weighing up to 100 pounds, has a five-point no-rethread harness system, and it turns into a lap-positioning booster for older kids. Comfort is key here: The car seat has zip-off backrest and seat cushions for extra padding, a four-position recline, a nine-position headrest that accommodates a growing child in both modes, and a contoured seat for total support. You can install it using LATCH connectors, and the car seat has built-in levelers to show you when it's installed correctly. And the cup holders are removable. NHTSA ease of use rating: 3 stars.
You get fewer options this car seat, which goes from a harness booster to a highback booster seat, but you also get serious ease of use. You can adjust the harness and headrest together, without any annoying rethreading. It fits children 22-100 pounds in both modes. It has a five-point harness system, dual cup holders, loop belt guides, and a 10-position height adjustable headrest. The car seat weighs 18 pounds. NHTSA ease of use rating: 5 stars.
Graco's popular booster seat grows with your child from forward-facing harness to highback booster to backless booster. The minimum weight is 40 pounds, and it's usable until your kid hits 110 pounds. It has a no-rethread harness system that lets you adjust the headrest and harness in one motion. It has two cup holders, which are removable, a machine-washable seat pad, body insert, and harness covers. It weighs just 15 pounds. NHTSA ease of use rating: 4 stars.
This is an entirely high-back booster seat, with a weight limit of 50 pounds. The cover is washable, it has two cup holders, and a five position adjustable headrest. Fancy? Not particularly. But it gets the job done. NHTSA ease of use rating: 5 stars.
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