Britax Frontier 90 Harness-2-Booster Carseat Review With Video

We are a Britax family – we have three Britax carseats, a Britax stroller and another Britax carseat at Mimi’s house. So when I decided it was time to move my big girl into a booster seat, my first choice was Britax. But which one? 

After much debate and research, I settled on the Britax Frontier 90. It had everything I wanted, and even some features I didn’t know I wanted until I learned about them. Thank you to Britax for providing a booster seat to review, now let me tell you all about why I choose this seat.

Britax Frontier 90 Harness Booster Seat ClickTight

When thinking about moving my daughter into a booster seat, my initial thought was to move her directly into a high-backed, seatbelt positioning booster. But the more I thought about it, and the more research I did, there was no way I was giving up the extra security of a five-point harness.

K is currently 5 years old, 43 inches tall and weights 39 pounds. For the last four years, she has been comfortable in the safety of her Britax Marathon. In reality, she could remain in her Marathon a bit longer, but her sister is fast out growing her Britax B-Safe carseat. So rather than buying the baby a new seat when big girl will need a booster soon, we decided it was time for everyone to get an upgrade. Baby girl to the Marathon and K to the Frontier 90. 

Britax Marathon B-Safe Carseats

The Britax Frontier 90 is a Harness-2-Booster meaning that it is really a carseat and booster in one. With the ability to use either a five-point harness or a seatbelt with the seat, my favorite thing about the Frontier 90 is its versatility. 

  • Five-point harness up to 90 pounds
  • Seatbelt positioning booster up to 120 pounds
  • Latch system up to 65 pounds
  • ClickTight system
  • Quick-Adjust No-Rethread Harness
  • True Side Impact Protection

Britax Frontier 90 ClickTight Installation System

I’m a big fan of the latch system. Having used a seatbelt to secure our carseats only a handful of times, I’ve never been able to get seats to feel as secure with a seatbelt as with the latch. So when choosing a booster a latch was my second requirement. However, the latch system is only safe up to 65 pounds, and I don’t plant to buy another booster seat in a couple of years. So I was intrigued by the option of the new ClickTight installation system available in the Frontier 90. Could a seatbelt really fasten the booster as securely to the seat as the latch? (I would have to see it to believe it.)

I am sure most parents will agree that carseat installation is a royal pain in the tush. Every time I have to move one of the seats, by the time it is installed I am sweating up a storm. Pushing, pulling, tugging and tightening. It is a workout to install a carseat properly. That ends with the Frontier 90 — no exaggeration. I cannot get over how easy it is to install this carseat using the ClickTight system. Just watch:


Open, thread, tighten, close, tighten, done. No sweat. No stress. I am in awe. And did  you see how secure that seat is — it’s not going anywhere. (Of course, to be sure we used the tether as well, but we tethered with the latch too.)

Number one selling point of the Frontier 90 — easy installation. 

Britax Frontier 90 ClickTight

As easy as installation is, you don’t want to be lugging this thing around for fun. It is a beast. At 28.5 pounds, this is a heavy seat. But I like it being a heavy beast — just think about all of the safety features this seat includes.

Quick-Adjust No-Rethread Harness

Another key feature of the Frontier 90 (that is new since the Frontier 85), is the Quick-Adjust No-Rethread Harness. Instead of having to remove the seat from the car to rethread the harness as your child grows (or when using with different children), the new feature allows you to adjust the harness height with the push of a button. (See video for details.)

Britax Frontier 90 5-point Harness Booster

Who is the Britax Frontier 90 meant for?

The Britax Frontier 90 is a forward-facing seat only, therefore, it should be used by children over the age of 2 and 25 pounds. Technically  this means baby girl will be able to use this seat later this fall. While I intend to keep her  rear facing in the Marathon as long as I can, it is nice to have that additional flexibility in a pinch. (Another reason to love the Quick-Adjust No-Rethread Harness.)


While I could go on an on about how much I love this seat, there is one con worth mentioning. In the last six months or so, I have finally taught  K how to unbuckle herself out of her Marathon. She pulls the release lever, unbuckles the clip and buckle and ready to get out of the car when I come to get her. (She can also buckle herself in with a quick spot check and adjustment from mom.) In the Frontier 90, she has lost the ability to unbuckle herself. The release lever for the harness is so far up under the seat, there is no way she can reach it, and she can’t unbuckle without releasing the tension. 

My guess is that this was done intentionally for safety reasons, for kids who like to maneuver out of their seat when they should not. But for a rule-obeying kid like mine who is old enough to unbuckle herself at the right time, it is disappointing to her and to mom. Not a deal breaker, but an adjustment for all. 

The Britax Frontier 90 is available in five color patterns, and is sold by Amazon for about $230. 

Britax Marathon Frontier 90 Carseat Booster

While Britax provided a booster seat to facilitate this review, we  purchased all of the other Britax carseats that we own. 

7 thoughts on “Britax Frontier 90 Harness-2-Booster Carseat Review With Video”

  1. While I am (happily) out of the carseat stage, I have to say–Britax carseats are the best. I love that they are becoming so much easier to install ans tighter/safer for the kids.

  2. I was amazed doing research on boosters that you actually don’t want them to latch in. That can harm the child since the booster with the weight of the child is supposed to move together as a unit in order for the seatbelt to activate and do it’s job in a crash. I also love the Marathon and will probably move next to the Frontier 90 when she’s too tall for this one!

    • I was surprised by all of the latch rules too when I started looking. For a tiny babe, they are great. But when you start adding in a bigger kid not as much. Soooooo happy with the Frontier 90!!! I can’t get over how easy it is to install!


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