Narrowest Booster Seats on the Market

Wondering which is the narrowest booster seat 2020 that can fit 3 across in the back? If you are looking for a narrow booster seat, you have come to the right place.

Having a narrow booster seat is helpful if you have multiple kids or if you have a small car. We have provided a list of some of the top narrowest booster seat on the market.

Remember that there are 2 types of booster seats: high back and backless. We have listed the best of each to help you decide which is right for your child.

It can be a challenge to fit multiple car seats in the back row of your car, even if you have a large SUV or minivan. That’s why it is helpful to find car seats that aren’t too wide, so that you can easily fit them into your car.

Top 10 Narrow Booster Seats

The below seats are great if you are looking to fit 3 in a row or if you just are looking for a narrow booster seat for bucket seats.

Narrow High Back Booster Seat

Here are the best narrow high back booster seats for small cars on the market:

Diono Radian 3RXT All-In-One Convertible Car Seat

The Diono Radian 3RXT is one of the best narrow booster seats. It is an all-in-one convertible car seat that accommodates your child in the rear-facing position from 5-45 lbs, in the forward-facing position with a 5-point harness up to 65 lbs, and in booster mode up to 120 lbs.

They are the only all-in-one car seats with a full steel frame, making them one of the safest and narrowest car seat on the market today. The seat is only 17 inches wide, so you can fit 3 of these car seats across in most mid-sized vehicles.

It is narrower than Diono’s other convertible and booster seats. For example, the Diono Pacificia, Rainier and Cambria are all 18 inches wide.

This car seat is comparable to the Diono Radian 3R, which is a little cheaper and has less weight limitation in the rear-facing and booster modes.

If you are parents of triplets or 3 children, you might want to try this popular seat out.

Graco Highback Turbobooster Car Seat

At a very affordable price, the Graco High Back TurboBooster child car seat is one of the narrowest high back booster that fits children from 30 to 100 pounds.

At just 16.5 inches wide, you can easily fit this into small spaces. If you need extra room, you can even fold the cup holders fold into the seat.

One of the best things about this seat is that you can easily convert this to a backless booster so that you can use it for longer as your child grows. This affordable booster seat goes a long way!

This toddler car seat booster features a multi-layer head rest and wide, padded armrests for extra support and comfort. The open-loops belt guides help to position your car’s seatbelt, making it easier for your little one to self-buckle.

Not only is the Graco Turbobooster one of the most popular booster seats, it is also one of the cheapest booster seats. You can typically find this booster seat for about $40!

Cosco Finale DX 2-in-1 Booster Car Seat

Made in USA with American and imported parts, this Cosco Finale car seat is one of the best slim booster seats on the market. Measuring 18 inches wide, it is designed to fit three across in most vehicles, perfect for growing families and car pools.

This slim high back booster seat with harness has extended use in both modes, fitting your child up to 65 pounds in its forward-facing with harness position and up to 100 pounds in the belt-positioning booster position.

The Cosco Finale DX  booster car seat is lightweight and easy to move from car to car, which is great for families on the go.

It features deluxe fabric that is easy to clean and keeps your child comfortable. You can also remove the seat pad, which is machine-washable and dryer-safe. The seat features a reversible cupholder, meaning you can detach and install the cupholder on either side of the seat.

Not only is this one of the best narrow booster seat for three across, it is also very affordable.

Evenflo Big Kid AMP High Back Booster Car Seat

At about 17 inches wide, you can use the Evenflo car seat to fit three car seats across in your vehicle. It is one of the best cheap narrow car seats available.

What’s great about the Evenflo Big Kid is that it can easily transition from high back to a no back booster seat, so you can use this seat for many years to come. It is one of the best narrow car seats to fit 3 in a row.

The Evenflo booster car seat has 6 position height adjustment, which you can easily adjust with one hand. It features dual, integrated cup holders that are built into the seat, which also helps save space.

Maxi-Cosi RodiFix Booster Car Seat


The RodiFix Booster by MaxiCosi fits children from 40-120 pounds. It measures 12 inches wide at its base and 19.5 inches at its widest point, so you can fit 3 across in the back of your vehicle.

It features Air Protect for superior side impact protection around your kid’s head. The RodiFix Booster has no arm rests, which make it easier to get your child buckled in, and it fits well next to wider seats.

Its belt routing system is easy enough to learn that children can buckle themselves in. RodiFix has LATCH connectors that hold the seat in place when the seat is not in use. This prevents the seat from turning into a projectile in the event of a collision. The LATCH is just to hold the seat in place; your child will be secured by a seatbelt.

The seat features front-access recline system, which allows seat and seatback to recline for comfort and better fit to vehicle. This belt-positioning booster also features a multi-height headrest and expanding side wings that grow with your child.

The stylish, premium fabrics are plush, comfortable, and self-wicking to help deodorize and draw liquids away from the skin. The RodiFix is quite expensive compared to many other boosters, but its premium features may be worth the price!

Narrow Backless Booster Seat

Below are the narrowest backless booster seat on the market:

BubbleBum Inflatable Booster Seat

The Bubblebum booster seat is one of the slimmest car seat on the market. This inflatable booster seat is only 13 inches wide so you can easily fit three car seats across the back seat.

It fits children from 40 to 100 pounds. In less than a minute, this blow-up booster transforms from a small pouch to a booster seat for kids.

It is foldable and portable, making it great for travel, car rentals, taxis, carpools, and caregivers. When it is deflated, it easily fits into a handbag or backpack.

This Bubblebum booster car seat can fit in the center seat of your 3-across installation even when nothing else seems to fit.

mifold grab-and-go car booster seat

The mifold booster seat is the most compact and portable booster seat on the market. You can fold it so small that it can even fit into a child’s backpack or your car’s glove box.

It is designed for kids 4 years and up, 40 to 100 lbs, and 40 to 57 inches tall. It fits 3 in a row, even in the smallest cars.

The mifold is great for vacation and travel. You will need this car seat for taxis and car rentals. Not only is it cleaner and cheaper than renting a booster seat, but you get to keep it!

Even though the mifold seat is 10x smaller than a regular booster, it js just as safe! Just because it is small doesn’t mean it is less safe than other seats. The mifold has been safety tested and meets or exceeds NHTSA standard FMVSS 213 in the USA. It protects your child by adjusting the adult’s seatbelt to fit properly.

Graco Affix Backless Booster

The Graco Affix Youth Booster is a slim backless booster seat that fits children from 40 to 100 pounds and up to 57 inches tall.

There is a front adjustment that allows you to easily and quickly tighten the booster to the vehicle seat. There is a secure LATCH connection system that keeps the booster seat steadily in place when the seat is not in use and helps facilitate independent buckling.

Keep in mind that the LATCH is to secure the booster to the vehicle seat while the booster is unoccupied and you will need to secure your child in the booster seat with the car’s lap/shoulder belt.

Cosco Topside Backless Booster Car Seat

The Cosco is one of the top narrow backless booster seat. Its slim design allows you to easily fit three car seats across in the backseat of your car.

The Cosco Topside Booster fits children 40-100 pounds and from 43 inches to 57 inches in height. It gives your child the extra height they need in order to keep your vehicle’s seat belt properly positioned.

It features extra-plush padding, which helps to make long rides more comfortable for your child.

Graco Backless TurboBooster Car Seat

As mentioned above, the Graco Backless TurboBooster is a narrow car seat. It features padded, height-adjustable armrests and hide-away cup holders.

You can purchase the High Back TurboBooster seat and convert it to a backless booster so that you can use it for longer as your child grows. In the backless mode, it fits children from 40 to 100 pounds and up to 57 inches tall.

In conclusion, these are some of the top narrow car booster seats. Read here for more best booster car seats 2020.

Which narrow booster seat 2020 best fits your needs?