Weight: 22-40 lbs. with harness, 40-80 as belt positioning booster.
IIHS rating: Check fit.
NHTSA ease of use rating:
Booster mode: Three out of five stars.
Harness mode: Two out of five stars.
Pros: Inexpensive, fits great in cars, five-point harness option from 22 to 40 lbs., headrest, armrests, storage bag.
Cons: Straps twist, poor ease of use.
Comments: The Cosco Highback Booster is a combo booster with a five-point harness from 22 to 40 lbs., then works as a booster from 40 to 80 lbs. Sounds like a good deal for $50, right? But this seat has cut corners at every turn. First and foremost, the top harness slot is just 14.75″—that means lots of kids will be too tall for this seat before they reach 40 lbs. Second, the tether strap is a total pain to adjust and get tight.
The Cosco Highback has been on the market for quite a few years, but it’s still not one of our favorites. While most parent feedback on this booster is positive (mainly because of the price), the government only gives this booster three out of five stars for ease of use. We’d agree: there are better options out there.