Best Car Seats That Fit 3-Across

When purchasing a car seat, it’s important to get one that fits ALL of your needs. With one child, this is pretty easy. You want something that’s appropriate for your child’s age and size, fits in your vehicle, and has the extra features you’ve been hoping for.

However, the more car seats you add to the equation, the more complicated choosing car seats becomes. One car seat is a breeze, two car seats is usually still simple, but three car seats can feel impossible. But worry not, moms and dads – we’re here to help. 

There are so many factors that can make getting correct installation difficult when you need to fit three seats in the second row. This is why getting a special narrow car seat designed for easier 3-across car seat installation can make the process A WHOLE LOT EASIER! 

So, today we’re sharing our list of car seats that fit 3-across in many vehicles. As always, we’ll only share seats we like and recommend! Then, we’ll give you some tips to get a safe and secure installation on all these seats! Let’s get into it!

Best 3-Across Infant Car Seats

Century Carry On 35 LX

At 17 inches wide, this infant car seat can fit well in some pretty tight spaces. The carrier is lightweight at just under 7 pounds, and the base is also simple to use and install.

We love this seat’s compact footprint front-to-back in addition to its narrow side-to-side profile. It’s an excellent option for preemie parents. And the cover is made of recycled water bottles, making it a sustainable option too. How cool is that?! Century infant car seats are compatible with Century brand strollers, which offer a growing lineup of versatile options.

Graco SnugRide SnugLock 35

Graco’s SnugLock technology is especially useful in a three-across setup! If you’re a parent who’s tried to squeeze three kids into your backseat, you’ve probably realized how little space is left in that center seat with two car seats installed on the outside seats. If you could just tug those side seats a couple of inches closer to the vehicle door you’d be set, right? Well, that’s easy to do with SnugLock car seat bases. The robust seatbelt lock-off lets you shift that car seat base slightly off-center on the vehicle seat, opening up valuable inches next to it for another car seat.

Between the SnugLock feature on the base and its narrow profile at 17.5” wide, this infant seat is a good bet for many three-across setups!

Graco SnugRide SnugLock 35 Review: click here

Nuna Pipa RX

This infant car seat is both narrow and lightweight – it’s 17 inches wide and weighs just about 9.5 pounds (not including the seat base.) And like the previous seat, it also has a seatbelt lock-off that can make it easier to install in the perfect spot to squeeze three kids in the backseat. All of these features make the Nuna Pipa RX an ideal choice when managing three kids in car seats.

Beyond the installation benefits, you may also choose the Nuna Pipa RX because of its premium non-toxic materials, its full coverage magnetic “sky drape” canopy, and its supportive infant inserts. We also love the Rigid Latch and load leg features, which can help absorb forces during a crash. The Nuna Pipa RX also fits all Nuna strollers and a variety of other stroller brands with the proper adaptors.

Read our Nuna Pipa RX review here. Watch our YouTube Video: What’s The Best Baby Car Seat? Nuna Pipa RX vs. Clek Liing

Chicco KeyFit 30

The Chicco KeyFit 30 is another narrower car seat at 17 inches wide. These half-inch measurements might not feel like much, but sometimes a fraction of an inch is all you need to get that perfect fit! Other reasons you’ll love your Chicco KeyFit 30 are it fits any Chicco stroller (and a variety of premium stroller brands with separately purchased adapters) and it has a removable infant insert. It includes a canopy, and the seat pad is completely machine washable. We also love how user-friendly this seat is, with only a couple of easy adjustments to make as your child grows!

Clek Liing

For a premium infant car seat choice, the Clek Liing has the features you need and want with a width of 17 inches. It also has a very small front-to-back footprint, measuring as one of the most compact infant seats on the market. It’s not as light as the Nuna Pipa RX, but it’s not the heaviest seat on the market either. The Clek Liing carrier weighs in at 10.5 lbs. And it’s another seat with a robust seatbelt lock-off, making installation a breeze!

Beyond the narrow fit, the Clek Liing has advanced safety features like Rigid Latch and a load leg. Plus, all Clek car seats are free of brominated and chlorinated flame retardants, and there are upgrade options for completely flame retardant free fabric. Like several of our other favorite infant car seats, the Liing can be used with a wide variety of strollers! 

Read our Clek Liing review here.

Install Clek Liing YouTube Video here.

Best 3-Across Convertible Car Seats

Graco SlimFit3 LX

As the name suggests, this “slim fit” car seat is great for 3-across situations. It’s 16.7 inches wide, has no-rethread harness straps, and an integrated lock-off for easy forward-facing seat belt installation. All of this makes installation and adjustment much easier, no matter where your SlimFit3 LX is installed. You can even remove the cover without uninstalling thanks to some strategic snaps and Velcro — so you can clean your car seat without taking it out of the car. (If this seat ends up in the middle, you’ll definitely want this feature.) 

We wouldn’t normally suggest purchasing a convertible car seat for a child who’s already forward-facing — because you’d be paying for a rear-facing feature you don’t need —but the slim, narrow profile of this seat combined with the forward-facing seatbelt lock-off make it one of the overall best choices for three-across, even for a child who’s past the rear-facing stage already.

While the SlimFit3 LX has a 5-pound minimum, it’s not a seat we’d recommend for a newborn due to its fairly upright posture, even when it’s fully reclined. But it’s a great option for growing babies who need to upgrade from their infant seat, and with forward-facing and user-friendly high back booster mode, it’ll last a long time! We also love that the Slimfit3 LX has two optional, removable cup holders — and they don’t add much width to the body of the car seat, so they actually fit even in most three-across setups!

SITS Note:

If you’re purchasing a Slimfit3 LX, make sure you get the right seat! Graco also has car seats named the Slimfit 3-in-1 and the Slimfit LX 3-in-1; confusingly, both of these models are pretty wide and are NOT three-across friendly. Look for the number 3 in the middle of the Slimfit3 LX name!

Cosco Scenera NEXT

Some of you may be in a situation where you need to buy 3 new car seats to make the 3-across situation work. As parents, we understand that this can be both stressful and expensive! If you’re intimidated by the price tags of some of these car seats, let the Cosco Scenera NEXT save the day. This car seat is $60.00 and is quite narrow at just 17 inches. 

The Cosco Scenera NEXT is a simple, bare-bones car seat, but that’s exactly why we love it! It’s easy to install and use, it fits average-sized newborns well, and it can allow most kids to rear-face until about three years old with its 40-pound, 40-inch rear-facing limits. (Rear-facing riders must also have one inch of head clearance in this seat — this applies to almost all rear-facing seats, but we mention it here because it’s the first way a long-torso’d toddler can outgrow this seat.) We also like that it’s easy to clean. The cover is machine washable and dry-able, and the cupholder can go in the dishwasher. 

This handy and inexpensive convertible car seat is also lightweight and perfect for parents who remove it often to travel. The Cosco Scenera NEXT is one of our favorite seats for air travel, and you can read more about car seat airplane tips on our blog. 

Read our Cosco Scenera NEXT Review here.

Safety 1st TriMate

This new addition to the market is another budget-friendly seat designed to fit 3-across in most vehicles! As far as cost and longevity, it’s a great middle ground between the inexpensive Cosco Scenera Next and the pricier options on our list. At 17 inches wide with a nice square profile and a price point of $140, it fills a big hole in the market as far as mid-priced narrow car seats. This seat rear faces to 40lbs and 40”, it has a no-rethread harness that’s super easy to adjust, and it can also be fairly compact rear-facing for babies and toddlers who can sit independently. And it fits average or large newborns too!

The biggest drawback of this car seat is the short harness height. The harness only gets 15 inches tall, which means taller or long-torso’d children could outgrow this car seat forward facing around 4 years old (though small and average kids should get a bit more use from it!). This is a bummer, especially for parents who want to find the longest-lasting 3-across configuration possible so they’re not stuck finding a whole new solution when one seat is outgrown. However, we still value this seat for its other features and its accessible price point. And it just might meet your toddler’s needs for a few years before you need to upgrade!

Britax Poplar Convertible Car Seat

The Poplar is the newest seat in Britax’s line-up and it’s about 17″ wide! It features Britax’s signature ClickTight installation system, making it super easy to install with the vehicle seatbelt and you can easily move it to the side by an inch or two to maximize that backseat space. The rear-facing limit is 50 pounds and 49″, which is the highest limit available in the narrow car seat category!

All of the fabric options are made of Britax’s SafeWash fabric, which is free of flame-retardant chemicals. The cover is machine washable as well. In the near future, it will be possible to purchase an anti-rebound bar for this seat as well.

Clek Fllo Convertible Car Seat

We can all agree that Clek is definitely not the most affordable brand. Still, we cannot deny that the Clek Fllo has some great features for the right buyer. For 3-across purposes, the Clek Fllo is one of your best options! It’s only 17 inches wide with straight lines and a boxy shape, so there are no unnecessary curves to interfere with side-by-side installation. And as one of the only seats on this list to feature a 50-pound rear-facing weight limit, it’s one of the best options for parents with high-percentile kids in their three-across mix!

The narrow fit isn’t what makes this car seat pricey, though. The Clek Fllo has advanced safety technology, including an anti-rebound bar and Clek’s patented EACT energy management system, which really set this car seat apart. All colors of the Clek Fllo, as mentioned earlier, have Clek’s high-tech fabric free of brominated and chlorinated flame retardants with options to upgrade to the flame-retardant-free fabric.

Clek Foonf

Here’s another Clek model. This one is also 17 inches wide and specialized for a good 3-across fit, with a similar external profile as its sibling, the Fllo. This model includes Clek’s most advanced safety features, like their REACT energy management system, an anti-rebound bar, and extended rear-facing capabilities for kids up to 50 pounds.

The Foonf differs from the Fllo in a few major ways: the Foonf is currently the only car seat on the North American market to feature a Rigid Latch for forward-facing harness mode; the Fllo doesn’t offer this feature. And the Foonf also has a separate wedge-shaped base that must be added to the bottom of the seat for rear-facing installations. This makes it sit a couple of inches higher than the Fllo and makes it a bit more compact front to back as well — the Fllo, in comparison, has a flip-foot on the bottom of the car seat that parents must position in the rear-facing position when installing in that direction.

Finally, the Foonf has adjustable recline settings, while the Fllo’s rear-facing recline is adjusted by manually shifting the car seat on the vehicle seat. Both are great options for three across, and we hope this rundown of the differences will help you decide between them!

Clek Foonf review: read here.

How to install Clek Foonf rear-facing: YouTube Video

How to install Clek Foonf forward-facing: YouTube Video

Best 3-Across Combination Seats

Chicco MyFit

The Chicco MyFit converts from a 5-point harness front-facing seat to a high-back booster for kids. This seat is for kids who are at least 2 years old, but remember that we recommend first rear-facing as long as possible. It’s 17.5 inches wide and has a built-in lock-off for easier seat belt installation. The cover is machine also washable, and the seat has 4 recline positions, depending on your child’s age and size. 

The integrated cup holders can be folded inwards so that they do not interfere with your 3-across plans. And the seat has 2-layers of padding for a super comfortable ride. If you want more from your Chicco MyFit, upgrade to the “Zip Air” model with zip-off fabric, an extra layer of padding, and an added kid storage console. 

Read our Chicco MyFit Review here.

Cosco Finale

The Cosco Finale has a unique shape that allows it to fit nicely in a 3-across situation. It’s 17 inches wide but still includes a cup holder that likely won’t get in the way. Cosco brand is known for being inexpensive, so that’s also a plus for the Finale. It also has a machine-washable cover.

Best 3 Across Booster Seats

Graco TurboBooster 2.0 Highback Booster

This high-back booster has inches where you need it and none where you don’t. It’s nice and tall to keep your child in the ideal position for safe riding once they’ve grown out of the front-facing harnessed seat (5+), but aren’t ready to graduate out of car seats altogether. This booster is only 16.5 inches wide, so it’s a good bet for 3-in-a-row car seat situations. 

This booster comes with cup holders, but you will need to fold them into the seat in most cases when fitting 3 across. It also converts to a backless booster, so there’s no need to find another 3-across-friendly booster when they’re ready for the next stage.

Peg Perego Viaggio Flex 120 Highback Booster 

The Peg Perego Viaggio Flex is one of our favorite narrow boosters. It folds completely up for easy traveling and is especially beneficial if you are a frequent flier, you use public transportation, or your seat moves between vehicles often. When installed, it’s just 17 inches wide, and it takes up no extra space. The cup holders pull out, so they can be retracted if there’s not enough room in your 3-across situation. 

Despite it being a booster, the Peg Perego Viaggio Flex allows you to get the right fit with multiple recline positions and tons of adjustment opportunities between the headrest, upper backrest, side wings, and seat. This seat is suitable for children between 40 – 120 lbs who are at least 5 years of age.

Read our Peg Perego Viaggio Flex Review here.

Cosco Rise

This is as simple as it gets. The Cosco Rise is an inexpensive low back booster that’s the narrowest on our list at 15 inches. It doesn’t have any of the extras, but it gets the job done. In addition, it fits children 40 – 100 lbs and weighs just around 2 lbs. If you are considering moving your child out of a booster seat because you can’t make it fit, don’t! Instead, opt for the Cosco Rise! 

Cosco Rise review here

Other 3-Across Options

RideSafer Vest Travel Car Seat

The Ride Safer Vest is not technically a booster seat, nor is it really a car seat. It’s an alternative that comes 100% approved by Safe in the Seat and other car seat experts. If you absolutely cannot make any other seat belt positioning methods work because of your car’s size or the required seats, the Ride Safer Vest is your best bet. The vest manipulates your car’s standard seat belt to fit safely around your child.

Since the Ride Safer Vest is an alternative to the car seats you’re used to, it is a bit of a learning curve. However, it’s super lightweight and portable and has sizes for kids up to 110 lbs. It’s not a “forever seat” like you may have now, meaning you’ll have to buy a new vest for every 15-30 lbs your child grows. But, all-in-all, the Ride Safer Vest will work for any 3-across situation because this restraint system is only as wide as your kiddo!

Read our Ride Safer Travel Vests Review here.

6 Tips for Installing Car Seats 3-Across

1. Determine how much room you have in your car. 

Before you start shopping, figure out how much room you’re working with. You can look in your car seat manual or Google your car’s make and model and the phrase “hip space.” This will give you the width you have to work within each seat. Or, if you have bench seats, it’ll give you the total width for the whole row. Though this number is a good base point to determine the width of the car seats you’re looking for, it’s not the only deciding factor. 

Additionally, if you find that you have very limited back seat space, you may very well need to upgrade to a larger vehicle. You don’t need to jump to a big SUV or van with a third row just to avoid putting a child in the passenger seat. But, to get everyone safely in the car, you may need to get something with a little more hip space in the second row. Assuming you have a vehicle with an adequate amount of hip space, look for car seats under 17.5 inches. 

2. Check the buckles.

Next, remove all the car seats from your car and buckle all the seat belts into their coordinating buckles. You need to do this to determine whether or not you have overlapping seat belts. They’re uncommon, but we’ve seen them out there! Car seats cannot be installed with any overlap, so if you do have overlapping seatbelts, it may alter your final configuration.

3. Consult the manuals.

Vehicle manuals are an essential piece to planning your 3-across arrangement. The manual will show you all the approved car seat positions for each seat. For instance, you can probably place an infant car seat in any back-row seat since it just requires a seat belt or LATCH anchors. However, a front-facing seat may only work in a couple of seats, because of the need for a top tether anchor. So if you’re working with front-facing car seats, their placement will be more limited and affect your final seat map. The manual will tell you where your anchors are!

4. Map out your options based on compatibility. 

Now, it’s time to plan your seating arrangement. Figure out all the safe car seat configurations and then go with the one that works best with your lifestyle. These options may not include your preferred arrangements, but it’s important to prioritize safety and compatibility over convenience. 

5. Opt for seat belt installation. 

Even if your child is the right weight and age for a LATCH installation on a rear-facing car seat, we recommend opting for the seat belt installation option. It allows for a little more room when squeezing three seats together. Plus, children outgrow the LATCH installation system quickly, so using the seat belts will ensure you don’t have to go through the hassle of a complicated 3-across installation again soon. 

6. Ensure each car seat is installed independently. 

Each car seat must be installed using its own manual and specifications. The car seats should not be able to move more than one inch in any direction after installation.

In addition, the car seats cannot be braced against one another to prevent movement. This creates the illusion of a proper installation when really, the car seats are dependent on one another to stay in place. This is very dangerous in a crash, so install each car seat independently.

If you need to fit 3 car seats in a row, opt for one that’s less than 17.5 inches wide. 

Choosing a car seat is hard enough, choosing a car seat for a 3-across situation is even more difficult. We hope this post helped make the process easier and answered all your burning questions. If you’re still having trouble, try one of our car seat buying kits or meet with one of our car seat consultants. Our certified car seat safety techs can evaluate your specific situation and help you get the right fit for your situation.

And in the meantime, parents can browse the Safe in the Seat Blog and YouTube Channel for essential and accurate car seat safety information. See you there!

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