Britax Roundabout 50 Convertible Car Seat, Onyx

Britax Roundabout 50 Convertible Car Seat, Onyx

The high safety ratings comfort and convenience of the Roundabout is great for children either in rear facing position from five to pounds or children in the forward facing position from at least one year old and pounds up to pounds The compact size is also ideal for use in vehicles with limited rear seat space

Main features

  • Convertible rear facing five to 35 pounds and forward facing from at least one year old and 20 pounds, up to 50 pounds
  • Side impact protection distributes crash forces, shields from vehicle intrusion, and contains the head and body
  • Higher forward facing seat capacity allows children to remain harnessed up to 50 pounds
  • Tangle free, five point harness with four harness heights and three buckle positions for a snug and secure fit
  • Premium push button lower latch connectors for a quick, simple and tight installation

Verified reviews


Easy to pinch thighs in buckle

This seat is adequate. Our objections follow. The buckle sits very low to the seat, with no possibility of pulling it out further. So, it’s very easy to pinch the baby’s thigh in the mechanism when you’re struggling to get her in. There is a “belly pad” (more like a “crotch pad”) to prevent this, but it’s not easy to flare it out properly across the crotch and inner thighs. This is especially true when you’re trying to make sure the child’s head doesn’t bump the top of the doorway as you put her in (not easy, as the chair sits very high in the car) and the buckle/belly pad is flopped over facing down in the seat. Also, we had a problem of the shoulder strap catching a hook in the back, preventing it from being loosened or tightened. We fixed it after struggling to remove and replace a plastic shield covering the whole mechanism behind the seat. Our other objection is that the seat seems overly complex, overly engineered in the wrong places, and unintuitive, with belts and buckles galore for every conceivable attachment possibility. In simpler matters, like making adjustments to the shoulder height and removing the cover to wash it, this thing is maddeningly complex. The directions are a voluminous mess, full of legalese and in many languages, so it’s hard to find the standard installation method in English. (We have a Honda CR-V with the shoulder belt; I would think this is the type of seatbelt that most people have these days; installation directions should put this one up front.)

Sallie Spotswood, NJ

Wonderful seat, but not for a newborn/infant.

After doing much research on Britax seats I decided this was the seat for us. I have been told it was made with the shell of the Marathon stripped down. I would best describe it as a stripped down Decathlon (which is made from teh same shell as the Marathon). It is a very affordable, safe seat to use with a child.Pros of this seat:**The seat pad is nice and cushioned. Baby loved the seat.**Just like the Decathlon, this seat has a 3 position crotch belt placement (Marathon does not have this).**Reclines FFing upto 33lbs. I have been told Britax do not recline FFing but in the manual it does state a FFing recline up to 33lbs. At 33lbs it needs to be in the straightback position. My 2.5yo is just about to hit 30lbs.**A lot of room for growth. I placed my 2.5yo in this seat and he has 2 more harness slots before outgrowing the seat.**Affordable. Even though it is only missing a couple features (**see minor cons**, this approx $80-over $100 cheaper than their higher priced modelsCons:**Can’t be used with an infant. The shoulder harness slots must be at or below their shoulders to be used properly. With this seat my 4mo (approx 28″) is about an inch shorter than the shortest slots. We still have an infant carrier that he has about 5″ before outgrowing.Minor Cons: These are things the Marathon and Decathlon have, which makes this seat stripped down version.**No HUGS. Not a big deal for me. They just ensure the chest clip is level with the armpits and not at the belly.**No shoulder pads. Technically using the shoulder pads from the store that many use void the warranty of the seat, and the straps are a little rough.** No seatbelt lock off. This Britax does not have it built in, but does come with a locking clip. I have used the locking clip in the past and have no problem using it. If you use LATCH, then you won’t need either until your child reaches 40lbs.**Harnesses to 50lbs and not 65lbs. Again not a problem. My 6yo weighs 40lbs. Most kids outgrow the Marathon and Decathlon heightwise before they reach the 65lbs. So this seat is very practical.

Elise Brant, NY

(4.5 stars) A very good choice for safety and value

The new Roundabout 50 is a very useful addition to the Britax line, if it matches what you’re looking for. It’s a somewhat compact seat with the safety and convenience features Britax offers (though with a couple convenience feature changes). And it’s Roundabout-level price makes it a very good value, as a safe seat that will have a long useful life.The notable differences vs. the original Roundabout is that this model can handle a child of up to 50 lbs, and up to 49 inches in height. (The original Roundabout was 40 lbs and 40 inches.) Given that a lot of children will outgrow the height of the chair before they outgrow the weight, this provides another somewhat compact option for parents, and lengthens the amount of time the chair is useful.By the way, this seat is a “Roundabout” only in concept – a somewhat compact, moderately priced seat (compared to the rest of the Britax line). It isn’t physically a version of the original Roundabout. Reportedly it’s actually based on the Decathlon, and it does have the same overall dimensions and weight and very similar details like strap heights. (Though the Decathlon has the extra HUGS padding and more pillows.) So you may want to read comments on the Decathlon, too, if you’re wanting more info on this new model.Other important differences relative to the earlier Roundabout:- Larger (19.5 W x 27.5 H x 25.5 D vs. 18.5 W x 24.5 H x 24 D).- Bigger seat area (9.5 D x 11.5 W, vs. 9 D x 11 W)- Heavier (15.5 lbs vs. 13.1 lbs.), but still lighter than many seats.- Four harness slot heights, so seated shoulder height of 10.75″ (rear facing) to 16.25″ (forward facing), vs. three heights with a range of 10.5″ to 15″.- Three buckle strap depths (2.4″, 4.4″, 6.4″) rather than just one (6.6″).There are a couple features the Roundabout had that you may miss having on the Roundabout 50:- The Roundabout 50 does not have the push button harness adjustment, which many parents really (really) liked on the original Roundabout. Instead it uses a lift lever.- The Roundabout had built in belt lock offs, while the Roundabout 50 uses a locking clip. (We use the LATCH system on our own cars, the lockoffs were nice because they were easy to use on rental cars, but I imagine we’ll adapt.)I don’t find any of these seats especially compact, though! We have a large station wagon and the back seat is very crowded with two. So you’ll want to research how it fits in your specific car – since this model is new, perhaps see what people say about the Decathlon and your car.We bought a 50 to use as our older child grows, and we’ll use the smaller original Roundabout for the younger child, to help a little with the space in the back.We did use another car seat (with a base and a detachable bucket) for the first several months, because we found it easier to put a newborn baby in the seat in the house and use that to carry her around in that, than to try to use a seat permanently installed in the car. So I can’t say what it’s like to use either of the Roundabouts with a newborn.And just a reminder to keep your child rear facing well past the old 1 year / 20 lb guideline, if your circumstances make that at all possible – a quick web search will give you the safety facts. This larger seat will help somewhat with making that possible.

Arline Maurice, IA

Love This Comfy Cow

We purchased the Roundabout 50 after comparing all the items in the Britax line. We could not justify paying the extra $100 for the Marathon when it seemed as if there weren’t $100 worth of differences between it and the Roundabout. I knew that our daughter would hit the height requirement before the weight requirement, so the extra 15 or so pounds the Marathon can hold would not be a worthwhile investment for us. We are incredibly happy with the Roundabout, and especially with all the different adjustments we can make. The shoulders have 4 different height adjustments, and the crotch has 3 different slots. We cloth diaper our daughter, so it is great for her extra cushy butt. It will also be good for her to grow into. The material is so luxurious and plush – she seems very comfortable while sleeping in it.Recently we installed a new Cosco hand-me-down (seems like an oxymoron, but our cousins gave us a convertible carseat they never used) in my wife’s car. Using that carseat has made me appreciate the Britax so much more. The clasp across the chest is a more secure fit, the strap adjustment button is so easy to push (not to mention the straps slide easily), the material is made of much better quality, and it is so much more padded. Our other carseat also doesn’t seem safe – the first day she was in it, she fell asleep, and when my wife got home she realized her head was hanging off the side of the carseat (this hasn’t happened since the first time, so it may not be a design flaw)! So I guess I am trying to say that the sides of the Britax come out further, keeping the head in.We prefer the Roundabout so much more that we are dropping another $160 to replace the Cosco. They have changed the design and have upped the new Roundabout to 55 lbs – yay! They also added the HUGS pads for comfort. The new Roundabout 55 has side impact wings – another plus. More carseat for the same price! My only complaint is that the new one does not come in the fun Cowmooflage print. 🙁

Jenna Glen Carbon, IL

2nd Britax Roundabout for me

I own the original version, which I purchased last year (and I reviewed it here). What I loved about the original was the compact size and super safety ratings. What I did not know at the time (chaulk it up to first time parent) is your kid can max out at 40 lbs. and may not be tall enough for a booster seat.I have ‘Irish twins’ so I moved my 4 month old from his Graco Snap and Go to the Roundabout (rear facing). I put my 14 month old in the Roundabout 50 forward facing – he’s north of 20 pounds and more than a year. I know some people keep their kids in longer, but he seems uncomfortable with his feet against my real seat.The installation is super simple with the latch system and trunk anchor.I picked up a weird pattern at Target for $149 – sale price in this week’s circular.

Earnestine Vega Alta, PR

Easy to use

Hopefully I’ll never find out how well this seat does in a crash, but everything else seems to be good. The seat was easy to install. Easy to adjust the straps, easy to get in and out of…just plain easy to use.The one thing I would have liked to see was more padding (like the higher end Britax carseats). You can’t even buy the padding separately. When my daughter falls asleep, her head is practically at a 90 degree angle.

Dessie Maryland Heights, MO

Yes, yes, yes– THE car seat for precious cargo

When our son was ready to transition from his infant carrier to a convertible (“big boy”) car seat, we read all the Consumer Reports, asked friends and relatives, and then went to BRU to “test drive” all of them with our son. Suffice to say, we selected this seat, no question– it was absolutely the best, hands-down. We wanted something that could keep him harnessed longer, and accomodate a higher height than most of the other convertibles. AND, it had to be able to fit in my compact car. Remember that the weight limit is not as useful a measure of the lifespan of the seat as the height limit is– unless you have a really rotund kid, they are going to hit 48 inches well before they hit the 50 lb. weight limit.Unlike other seats on the market, the buckles on the Britax models are SO much sturdier and clip securely. With other seats, I found myself squeezing and squeezing the buckles just to get it “snapped” in properly– and this without even inserting the wiggling 7 month old! (And we confirmed this was not just the floor models at BRU by trying the same models out in other stores as well– we continued to experience the same phenomena)Many pinched fingers later, we were delighted to try out the Roundabout 50. Although the Britax brand is slightly more expensive, there are some things that are just worth the money. Those things being: crib, car seat, and stroller– no sense in “cheaping out” on these three necessities, since you will be using them every single day.In addition to the obviously higher-quality construction, I also appreciated the ease of installation (and so did the firefighters who initially installed it– I have since done it myself once), and the ease of removing and “reapplying” the cover (for those inevitable baby messes). Best part is that the Roundabout 50 fits in my car, a 2007 Toyota Corolla, easily, while still having ample room for our son to grow– this can not be said about many other brands.I think this is an excellent choice for children 15-50 lbs. We have since purchased another Britax model– Decathlon (to 65 lbs)– for my husband’s car, and I can actually say that after using them both for some time, I actually prefer this model, though it lacks some of the pillows and “plushness” of the Decathlon. We expect that both of these seats will make it through to our son’s 5th birthday at the least. We have had this seat for two months now, and I highly recommend it.

Muriel Pachuta, MS

Britax Roundabout 50 Convertible Car Seat

My family has about 5 britax’s and we are very happy with their products. This is a little more cheaply made than their premium models, but I can’t complain as I got a sweet deal on this, but I wish that the seat had a separate reclining part like a true car seat. My daughter loves the seat and the fact that it’s one of the safest makes me a happy person.

Angel Breeden, WV