Combination Car Booster Seats

Best five-point harness child booster seats

Experts say the safest way for kids to ride is in a five-point harness -- the type that's in your baby's car seat, with straps over the shoulders, hips and crotch. New "combination booster seats" have this type of harness built in. After your child outgrows the harness, you can use the seat as an ordinary booster seat with your vehicle's seatbelt.

The Graco Nautilus 3-in-1 (*Est. $160) is by far the best-reviewed combination car seat/booster seat on the market. This seat accommodates kids weighing 20 to 65 pounds in the five-point harness, and then works as a belt-positioning booster seat for kids up to 100 pounds. It can convert to a backless booster seat, but studies show that this configuration doesn't protect kids well in a side crash (see Introduction for more). With its back attached, the Nautilus has full side-impact protection, complete with head support and energy-absorbing EPS foam. Parents say this booster seat is well built and comfortable for toddlers and older kids alike. It also gets good marks for its sleek styling and unobtrusive color combinations. The only notable complaint about the Nautilus booster seat is its general bulkiness: It's 20 inches wide, 29 inches tall and weighs 26 pounds. While that's not a problem if you're installing a single booster seat, parents say it can be an issue if you need to use three car seats in a row.

The Britax Frontier 85 (*Est. $280) has similar specs to the Nautilus child booster seat, except that it accommodates kids up to 85 pounds in five-point harness mode. In booster mode, it can be used for kids up to 65 inches and 120 pounds. The Frontier booster seat has all the safety and comfort features you'd expect in its price range: EPS foam, side-impact protection, cushioned armrests and high-density comfort foam. There's also a no-re-thread harness to make adjustments easier as the child grows. That means there's no need to uninstall the booster seat, remove the harness, and then rethread it into a higher slot -- a process that many parents find inconvenient and confusing enough that they delay making much-needed adjustments. Like the Nautilus, the Frontier booster seat draws some criticism from parents about its size and weight: This may not be the seat for you if your space is limited or you plan to swap frequently between vehicles. The other obvious downside is price -- the Britax Frontier 85 booster seat costs almost twice as much as the top-rated Nautilus 3-in-1 car seat.

The Safety 1st Apex 65 (*Est. $125.) is a more modestly priced combination harness/booster seat. Like the Graco Nautilus 3-in-1, the Apex 65 booster seat works in five-point harness mode with kids weighing up to 65 pounds. However, one top reviewer points out that it has relatively low top harness slots, and its two-position crotch strap may be a tight fit for bigger kids -- a complaint we also found reflected in multiple user ratings for this booster seat at Amazon.com, where it earns a mediocre score of 3.5 out of 5 from nearly 40 reviews. Parents of tall, slim children (or those with smaller vehicles) also express reservations about the booster seat's wide width. We also found several complaints about its hard-to-tighten (and twist-prone) harness straps. Overall, considering the similarity in price, reviewers say this seat just doesn't measure up to the Graco Nautilus 3-in-1 booster seat.

The Evenflo Maestro (*Est. $80) offers a five-point harness at half the price of the Graco Nautilus 3-in-1 booster seat. Experts judge it just as easy to use as the Nautilus car seat, with just as good a seatbelt fit in almost all vehicles when you convert it to a belt-positioning booster seat. But that day will come more quickly with the Maestro than with the Nautilus: The Maestro's harness weight limit is 50 pounds, versus 65 pounds for the Nautilus. Both booster seats work as a belt-positioner for kids up to 100 pounds and 57 inches. Some Maestro booster seats cracked in a previous ConsumerReports.org crash test, but a recall and repair fixed the problem; see our Useful Links section for more.