Narrow Car Seats To Consider

There are many narrow car seats, others come in the form of a booster; some come in the form of a convertible, and many famous car booster brands produce them. It can be daunting to find the best one.

Keep your child safe and secure in their slim car seats.

To help you, we read reviews online of many convertible booster seats, infant booster seats, and booster convertible booster chair options, then made a list of the highly-rated narrow car seat from Amazon, so you can choose which one fits your needs. But what is a booster chair? A booster chair is a vehicle cushion so that your child can sit high enough to put the new belts on comfortably in your vehicle. This way, you can keep them safe and secure in their slim vehicular chair in case of an accident. Once your child is around 4 feet 9 inches tall or between 8 to 12 years old, you can already switch from an infant vehicular chair to a booster chair.

Are Slimmer Child Car Seats Necessary?

Vehicular belt positioning is more important than some people think. The shoulder belt is supposed to come across the chest and sit on the shoulder in a snug fashion. If you are transitioning a child from a narrow-width car seat that starts as an amazing infant child car restraint system and progresses all the way through to a backless one, then you need to pay close attention to where the shoulder belt should be so your child is as safe as possible.

If you read further, you will also learn useful tips and FAQs.

Why Would You Need A Slim Child Car Seats?

Most sedans can fit three persons on the back chair. Minivans can also fit three persons on the last row plus two in the middle row. A car seat or booster can tend to be bulky and space-consuming.  The narrow infant car seats will allow you to maximize the number of riders per row and they tend to fit better, especially behind taller drivers. If you’ve ever tried fitting three child car restraint systems across in your back seat, whether the narrowest car seat, the most advanced infant car seat, the widest convertible one, rear-facing, front-facing, a high back car booster seat, or backless and narrowest booster seats, many times, they just won’t fit side by side on your car seat.

But, it is possible! So, if you have a child who is ready for a high-back booster seat or one without a back, then you’re in the right place for help finding the best narrow car seat aligned properly for your vehicle.

Graco Tranzitions Car Seats

This is like a convertible booster chair that starts for use with a toddler and can be used to when there’s no need for a slimmer child car restraint system. It looks like a high-back booster infant seat and even has the 5-point harness straps with a harness mode which you’ll find in a traditional convertible kid’s narrow car seat. As your child grows, you can adjust the headrest and remove the inner padding and harness configuration so your older children can start using the infant’s chair belt to secure themselves. Eventually, you’ll also take the high-back booster seat portion off the child car restraint system as your child can only ride in the booster infant seat. These are not to be used as an infant booster seat, nor are they to be installed rear-facing. There are two cup holders and plenty of comfortable padding. Also, this has been tested and exceeded safety standards for side impact protection, rear impact protection, and frontal and rollover crashes.


One the best car seats

  • This narrow car seat offers superior protection for your child on the road. It can be used in 3 ways and can accommodate children from 22 lbs to 100 lbs.
  • This car seat is a good investment as it grows with your child and offers maximum convenience since it is simple to install and clean.

This is slim booster seat

Diono NXT Car Seats

This booster infant car seat isn’t meant to be used until children reach 40 lbs. It’s for kids who are older than the toddler stage. The Diogo Everett comes in 4 different colors. It has lots of padding compared to other car seats, so kids will be comfortable, but keep in mind there are no cup holders. It’s a high-back narrow car seat to start and then transitions to a backless booster later on. It works with the LATCH installation system built into most newer vehicles’ vehicle seats. It also has really good side impact protection for your child’s safety. It’s one best narrow boosters on the market for its high level of attention to safety standards and its slim, ergonomic design.


A Red slim booster seat.

  • The Everett has a slim-fit design for your car and is best for travel. Although this car seat is highly portable it does not compromise comfort and safety.
  • This car seat has essential and great features such as the 7-position headrest and buckle-friendly fit design that will keep your child relaxed and safe while you go on a journey using your car.

Slim booster seat headrest.


Cosco Finale DX 

The Cosco Finale is a great option of high back car seats for families on a tight budget. It’s affordable but is still a good quality slim booster seat. You can start using the high-back booster seat with children who are 30 lbs. It will work in the capacity of a forward-facing car seat convertible infant seat for an older toddler, not as an infant booster seat, and never in the rear-facing car seat position. Parents love this high-back booster seat for its price, but also for how light it weighs. It’s a reliable child car seat that’s easy to take with you wherever you’re going. You can definitely fit three car seats side by side in most autos’ rear car seats. You also get the convenience of cup holders, removable machine washable covers, and fully adjustable settings. All of this is topped off by the fact that it exceeds all of the safety standards set by governing agencies.


Federal safety standards approve of this child restraint system.

  • The Finale DX car seat has a sleek and innovative design at a reasonable amount. It also offers well-thought safety features that will put your mind at ease when driving with your child in tow.
  • This car seat has met Federal safety standards and is easy to move from auto to auto as it is designed to fit side by side and across the back seat of most vehicles.

Booster seat for kids


Big Kid LX 

The Big Kid LX High Back Booster car seat by Evenflo should be used for children who are ready to use the vehicle seat belt in your vehicle. No harness belt is built into this booster seat, so the vehicular belt is the only means to achieve secure and tight installation for your child’s safety. That means you should not use this car seat for a toddler. As your child grows, the car seat can be adjusted up to 6 different height levels. The seat is super easy to clean, too. These aren’t the slimmest options on the market, however, it’s one of our car seats best for slim autos because it is slimmer than most, and you can fit three of them across in some vehicles. Be aware that this slim booster seat is not LATCH system compatible. The only securing mechanism is the vehicular belt in your vehicle. It’s even recommended that you secure them in place with the vehicular belt when the child isn’t riding in it.

  • The high-back booster car seat has a very simplistic design that offers 2 modes of use. It also features 6 position height adjustment to accommodate your growing child.
  • It comes with 2 cup holders to allow your child to snack when going out for a long drive.Diono Radian 3R Booster Seat

Diono Radian 3R Convertible Seats

The Diono Radian 3R Convertible Car Seat and High Back Booster may be the slimmest car seat on our list. One of the greatest things about this one is it can be used as one of the narrowest convertible car seats that run from rear-facing mode infant car seat through to forward-facing big kid booster narrow car seat. Most of the time, the best convertible ones will start as infant car seats and stop after toddler age. Or, you’ll get a convertible one that starts as a toddler seat and goes through to the end as a narrow booster. However, the Diono Radian 3R Convertible Car Seats are different. They run the whole gamut.

  • A convertible booster car seat that can be used for 10 years.
  • Reinforced steel core has plenty of impact protection for keeping kids safe.
  • The Diono Radian 3R Car Seat is one of the narrowest seats on the market.
  • LATCH system compatible with seatbelt installation on your car.

When you have a house full of kids or if you are a mom driving an auto, you will need to fit a lot of kids in your vehicle. You keep going back and forth from home to school, soccer practice, or ballet rehearsals. Getting all kids in the vehicle will save you on gas. You can also save time, effort, and money finding a sitter to stay with the other kids while you drive around. A slim booster seat makes it so that you can fit everyone in all at once. You can opt for a narrow convertible booster car seat or go with a narrow booster seat that starts as a high-back car booster seat. Make sure you measure your vehicle seat and do the math to find out which slim booster seat will work in your auto.

A child sitting inside the car

Other Benefits Of Slim Seats

With a slim booster chair, you can save time, money, and effort. It can help by giving you enough space to fit three slim boosters. One thing also when you purchase a slim booster chair, you don’t have to worry about what type of vehicle you own now. If you have a small vehicle and need to fit three booster chairs for the kids, all you have to do is buy the slim booster chairs so that you don’t have to buy a new vehicle. That way you don’t have to replace the vehicle you already have. If your vehicle is super slim and you need to fit 3 chairs across, we recommend the Diono Radian 3R because they are truly slim for smaller vehicles.

Two key points to keep in mind are the space available for your current vehicle and flexibility. The cup holders and the outer shell design will affect how the chairs will fit in your vehicle. Make sure to consider these as well when buying the narrow booster chair to be able to fit them in your vehicle properly. Also when installing the booster chairs, install from the middle seat first.

Keep in mind, too, that you can get convertible seats or booster chairs, like the Diono Radian 3R which functions as an infant booster chair through to a backless booster chair. This kind of convertible booster chair will also help to save you money. You can use the same chair for the entirety of your child’s booster chair riding years with the Diono Radian 3R. The same is not true for other booster chairs that start at 40 lbs. per child, such as the Maxi Cosi RodiFix Booster Child chair with rigid LATCH connectors.

Slim And Regular Car Seats

You can also consider a slim booster car seat and a regular booster car seat combination. If you love traveling, you will need boosters with cup holders to fit the needs of your kids within their reach. They will need snacks and drinks. If you are driving or sitting up in the front seat, you won’t need to keep reaching back to give your kids what they need.

Three Narrow Chairs? No Problem!

If you have three kids, you can sit all three in the third row. The middle chair can be a slim booster. Regular boosters can be placed on each side of the slim booster chair. This way, each child can have a cup holder within reach, even the child sitting in the middle!

Three children sitting inside the car

The best thing about this seating arrangement is that you will not need to separate one car seat of one child from the other. They can all bond sitting side by side in their slim infant chair.

Two Narrow Chairs? No Problem!

If you have two kids and have a bench sitting on the 2nd row, it will be a squeeze to put two booster chairs. You will need one narrow car seat and one regular booster chair. This way, your kids are sitting closer to the front seats, and you do not have to separate them by putting one child in the third row.

If you have bucket center seat positions in the second row, you won’t have a problem fitting two regular boosters. However, using slim booster chairs or convertible infant chairs, like the Diono Radian 3R, will help younger passengers put vehicular belts on easily even in the center position. They do not have to keep moving their boosters out of the way to buckle their belts.

The mother is teaching her child how to use a booster seat.

One Kid And A Lot of Gear? No Problem!

A slim booster chair can be helpful even if you only have one child. You will have more space for your gear or your child’s things on the chair. Also, when grandparents come along or someone else, there will be more legroom for them to sit.

All in all, it is really useful to have a slim booster seat! No matter the number of kids or the amount of gear you have, more space is always good. You can get a slim convertible infant seat which is also a narrow car seat that you can use as an infant booster car seat. You can have it grow with your child properly into a slim infant chair booster later on. There are plenty of options that will meet your needs and your budget.

Car Seats – FAQs

Which Graco Child Car Seats Is The Slimmest?

Is A Slim Fit Car Booster Seat Safe?

Ensuring the safety of slim-fit child car restraint systems is paramount. While many of these designs are secure, it’s essential to carefully assess factors like weight limits, integrated lock-offs, and proper installation. This is particularly crucial for narrow or side seats. Keep in mind that wider car seats and combination seats can differ in safety features, including built-in lock-offs, locking clips, or crotch buckles.

Also, when grandparents come along or someone else, there will be more room for them to sit with slim booster seat.
When Can I Put My Child In A Backless Booster Car Seat?

Your child can sit in a backless booster once they outgrow their booster chair. It can happen between the ages of 8 and 12. The typical recommendation is for a child to be at least 40 lbs. before transitioning from convertible booster chairs to backless boosters.

Other than that, you can put your child in a backless booster when they outgrow a forward-facing car seat, meet the height and weight requirements, and the vehicle has proper seat belts, headrest, backseat space, and is a larger vehicle with no-rethread harness.

Can You Use Chair Belt Extenders With Booster Car Seats?

Vehicular belt extenders tend to alter everything from the starting point of the buckle to the shoulder belt’s angle. Because of that, you can never use them with boosters. It’s important that the vehicular belt is in the correct position to keep your child as safe as possible. The shoulder belt should be across the chest and sitting snugly on the shoulder, while the lap belt should sit low on the lap.

How Wide Is Booster Car Seat?

Booster chairs do not need to be too broad, to the point that they take up the entire backseat. A slim booster chair that’s 17-20 inches wide is already good. Some of the more narrow car seat options are 15 or 16 inches wide.

What Is The Slimmest Infant Booster Car Seat?

You cannot go wrong with UPPAbaby’s Mesa Infant booster chair. The base of this slim booster chair is only 15 inches wide. Another option is the Diono Radian 3R. It can be used as an infant booster chair to start but is a convertible booster chair that can be used for 10 years. It’s only 16 inches wide so it’s definitely one of the more slim booster chairs on the market.

What Is The Slimmest Booster Car Seat?

The slimmest booster chairs include (but are not limited to) Chicco Keyfit 30, Baby Flex Loc, Maxi Cosi RodiFix Booster Child chair, Graco TurboBooster Highback Booster Car Seat, and Diono Radian 3RXT. The choice merely depends on your budget and personal preferences.

Child booster seat that is 17-20 inches wide are already good.
Are High-Back Boosters Seat Safer Than Backless Seat?

Yes, high-back boosters are safer than backless ones because their features aim to protect the child’s head from most sides. Some units also have adjustable headrests to make your baby more comfortable. Your baby can also fall asleep on it peacefully with its vehicle’s seat belts. Backless booster seats are only supposed to boost the child higher in the vehicle seat so the vehicle’s seat belt sits properly.

How Do You Fit Three Car Seats In A Small Vehicle?

Fit three car seats in a small vehicle by optimizing seat belt installation, arranging the car seats strategically for leg room, considering the use of narrower car seats, and possibly using a rear-facing car seat as the only car seat if appropriate.

How Wide Is Graco SlimFit LX?

Can 3 Booster Seats Fit In An SUV?

Whether 3 booster seats can fit in an SUV depends on the narrowness of the vehicle seat and the specific dimensions of the boosters. This consideration becomes even more intricate when factoring in other variables such as additional car seats, two rear-facing seats, the compatibility with the vehicle seat belt, anti-rebound bar, seating positions, Clek car seats, and the presence of two car seats.

Can 3 Booster Seats Touch Each Other?

No, it is not recommended to have 3 child car seats touch each other, as most car seats have specific width requirements, and combining them may exceed the limits, compromising safety, especially considering seat pad thickness, seatbelt lock-off, and the rear-facing position, which can be further challenging with narrower seats and a taller driver.

Should The Child Car Booster Seat Go Behind the Driver Or Passenger?

Where Is The Safest Place For Rear-Facing Seats?

Is Rear Vs Front Facing Car Seat Safer?




Last Updated on May 12, 2023 by Rejie Salazar

DISCLAIMER (IMPORTANT): This information (including all text, images, audio, or other formats on is not intended to be a substitute for informed professional advice, diagnosis, endorsement or treatment. You should not take any action or avoid taking action without consulting a qualified professional.   Always seek the advice of your physician or other qualified health provider with any questions about medical conditions. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here a

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