7 Best Slim & Narrow Car Seats of 2023

Woman choosing child car seat for her baby in shop supermarket.

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If you have a small car or two or more kids, the width of a car seat may be one of the most important things to think about before you buy. Slim and narrow car seats are ingenious because they are safe and secure while also allowing you to fit your whole family comfortably in your car. 

Whether you have a newborn and a toddler, three school-age kids, or two little kids and a big kid, narrow car seats may be just the thing to help make your back seat safe but also more comfortable for all your young passengers. 

Any parent who’s ever tried to install a car seat knows how tricky it can be to lock it in. Add in a second and a third seat, and you might give up altogether. Another benefit of narrow car seats is that they allow you to maneuver in your back seat more easily and with less hassle. 

So buckle up and take a look at our list of some of the best slim and narrow car seats of 2023!

Best Choice
Graco Slimfit (Slimfit w/ 3-Across Fit, Katrina)
Best for Babies
Chicco KeyFit 30 Infant Car Seat and Base | Rear-Facing Seat for Infants 4-30 lbs.| Infant Head and Body Support | Compatible with Chicco Strollers | Baby Travel Gear
Best for Older Kids
Safety 1st Grand 2-in-1 Booster Car Seat, Forward-Facing with Harness, 30-65 pounds and Belt-Positioning Booster, 40-120 pounds, Black Sparrow
Graco SlimFit3 LX 3 in 1 Car Seat
Chicco KeyFit 30 Infant Car Seat and Base
Safety 1st Grand 2-in-1 Booster Car Seat
Best Choice
Graco Slimfit (Slimfit w/ 3-Across Fit, Katrina)
Graco SlimFit3 LX 3 in 1 Car Seat
Best for Babies
Chicco KeyFit 30 Infant Car Seat and Base | Rear-Facing Seat for Infants 4-30 lbs.| Infant Head and Body Support | Compatible with Chicco Strollers | Baby Travel Gear
Chicco KeyFit 30 Infant Car Seat and Base
Best for Older Kids
Safety 1st Grand 2-in-1 Booster Car Seat, Forward-Facing with Harness, 30-65 pounds and Belt-Positioning Booster, 40-120 pounds, Black Sparrow
Safety 1st Grand 2-in-1 Booster Car Seat

Our Choice: Graco SlimFit3 LX 3 in 1 Car Seat 

Graco SlimFit3 LX 3 in 1 Car Seat
  • Fits 3 car seats across, saving space in your back seat without compromising on the safety you trust and the features you need
  • 3-in-1 car seat grows with your child from rear-facing harness (5-40 lb) to forward-facing harness (22-65 lb) to highback booster (40-100 lb)
  • Measures 16.7 inches wide, with a spacious seat for your child’s comfort and a slim design for more room in the back seat
  • Graco ProtectPlus Engineered: a combination of the most rigorous crash tests that helps to protect your child in frontal, side, rear & rollover crashes
  • Designed to fit three across in your back seat
  • Grows with your child from birth up to 100 pounds
  • Easy to install
  • Lightweight
  • Comfortable for children
  • Expensive
  • Limited color options

Graco can be trusted to produce practical, safe baby products that just make sense. For example, the Graco SlimFit3 LX 3 is among the best narrow convertible car seats on the market. 

It’s specifically designed to fit three across in your back seat or to give you more space if you have a small car. Parents also find that despite being narrow, it gives kids plenty of room, and they find it one of the most comfortable car seats. 

It has three modes to stay with your child from birth up to the booster seat. It’s rear-facing from 5 to 40 pounds and has a forward-facing harness mode for 40 to 65 pounds. Then, when your child’s ready, it becomes a high back booster for kids up to 100 pounds.  

Parents are also pleased with how easy it is to install compared to other car seats. Another plus is that it’s lightweight, so if you need to switch seats between cars, travel through airports, or if you have a smaller car, it’s easy to maneuver the SlimFit3. 

On the downside, it’s pricey. However, considering that it should last you until the booster seat phase when your child is ten to thirteen years old, it’s worth the investment. You’ll only have one car seat to buy. 

If fabric design and color are important to you, you won’t find many options beyond black, gray, and dark plum. Considering the other advantages of this car seat, though, you probably won’t mind the limited color choices. 

Material: ‎Foam, Alloy Steel, Plastic, Fabric | Maximum Weight Recommendation: ‎100 pounds | Dimensions: 20.7 x 16.7 x 24.5 inches
View on Amazon | View on Walmart.com | View on GracoBaby.com

Best for 3 Across: Diono Radian 3R, 3-in-1 Convertible Car Seat

Diono Radian 3R, 3-in-1 Convertible Car Seat
  • 10 Years One Car Seat – from Birth to Booster (5 – 120 lb) it’s all you will need. Grows with your child, ultimate protection on every road trip. 4 modes in 1 seat!
  • Rear Facing for Longer – lovingly engineered to keep your child rear-facing up to 50 lb.
  • Fits 3-Across – our famous slim-fit design with zero compromises to safety, space, or comfort.
  • Mechanically engineered from reinforced automotive grade high-strength steel, our unique core shell shields and protects your child.
  • Can fit three across the back seat comfortably and safely
  • Adaptable from birth and should last until your child is in the booster phase
  • Rear-facing for longer, up to 50 lbs or about four years old
  • Heavy to maneuver
  • No cup holder for your child
  • Can be tricky to install

The Diono Radian 3R, 3-in-1 Convertible Car Seat is a narrow convertible car seat built to last. According to Diono, you should only have to buy a car seat once for all the years your child will need one, and this is the one! 

This narrow car seat is designed specifically to fit three seats across a car’s back seat safely, securely, and comfortably. Diono is the originator of the slim, three-across concept, so they know what they’re doing. The seat itself is suitable from birth and adjustable for children up to 120 pounds, more than most brands that are only safe for those up to 100 pounds. 

Not only that, but unlike many other brands, Diono has designed this car seat to be rear facing up until your child weighs 50 pounds or is about four years old. As a result, its rear-facing mode can be used for up to two years longer than most other seats, which generally switch to forward-facing at around two years of age. 

The Diono, however, isn’t a lightweight car seat. Parents report that they love many things about it, but it’s heavy and so can be a little tricky to maneuver. Some parents also find it somewhat difficult to install. There’s also no cup holder, which may be a problem for toddlers who often lose their cups and bottles in the back seat. 

Despite these minor issues, this is a good option if you’re looking for a narrow, convertible car seat to fit multiple kids in your car. 

Material: Alloy Steel, Polypropylene, Plastic, Polystyrene | Maximum Weight Recommendation: 120 pounds | Dimensions: 16 x 17 x 28.5 inches
View on Amazon | View on Walmart.com | View on Sears.com

Best for Older Kids: Safety 1st Grand 2-in-1 Booster Car Seat

Safety 1st Grand 2-in-1 Booster Car Seat
  • Forward-facing with harness, 30-65 pounds and Belt-positioning booster, 40-100 pounds
  • Designed to fit 3 across in most vehicles – great for growing families and car pools
  • Lightweight and easy to move from car to car
  • Deluxe fabric gives kids a comfy ride
  • Designed to fit three across in most back seats
  • Lightweight and easy to move between cars
  • Suits children from 30 to 100 pounds.
  • Reasonable price
  • Not suitable from birth
  • Forward-facing only
  • Can be tricky to install

The reasonably priced Safety 1st Grand 2-in-1 Booster Car Seat is a great narrow car seat choice when you’re trying to find the best toddler car seat. This is a good option for families who may need to use their infant car seat for their newborn and are looking for a good next seat for their toddler. 

Like the others on this list, this car seat is designed to fit three across in most cars. It’s also lightweight and easy to move between cars for carpooling or traveling through airports. 

It has two forward-facing modes for use depending on the weight and age of your child. For children weighing 30 to 65 pounds, it has a safety harness. For children 65 to 100 pounds, use it as a booster positioned with the seat belt. 

Children also find it comfortable, with an adjustable headrest and high-quality fabric covering. 

Some parents find it tricky to get the knack for installing the car seat. In addition, if you are looking to make just one car seat purchase for your child’s first 10 to 13 years, this is not a car seat that’s suitable from birth. The Safety 1st Grand 2-in-1 is an additional purchase for older children. 

However, it has a great price point, so the extra cost may not be as costly as you might think.  

Material: ‎Fabric | Maximum Weight Recommendation: 120 pounds | Dimensions: 30.19 x 19.63 x 18.25 inches
View on Amazon | View on Walmart.com | View on eBay.com

Best for Babies: Chicco KeyFit 30 Infant Car Seat and Base Best for Babies  

Chicco KeyFit 30 Infant Car Seat and Base
  • EASIEST INFANT CAR SEAT TO INSTALL – Simple, accurate and secure installation – every time – with two bubble-level indicators and spring-loaded leveling foot for proper base angle in vehicle seat and premium LATCH connectors for easy attachment.
  • COMPATIBLE WITH CHICCO STROLLERS – Infant car seat clicks securely into the stay-in-car base and compatible Chicco strollers for a convenient car seat and stroller combo. A two-position carry-handle and one-hand release make it easy to remove.
  • TOP-RATED INFANT CAR SEAT – Innovative SuperCinch Force-Multiplying LATCH Tightener helps achieve a secure fit in the vehicle and the carrier shell is lined with EPS energy-absorbing foam for improved impact protection
  • FROM DAY ONE – Car seat includes a removable infant head and body support insert to accommodate newborns and smaller infants on their first rides. The Chicco KeyFit 30 Infant Car Seat is designed for babies between 4-30 lbs. and up to 30” tall.
  • Easy to install
  • Adjustable canopy
  • Washable seat pad
  • Compatible with Chicco strollers
  • Only suitable up to 30 pounds
  • Your child is likely to outgrow it quickly

For a small car or a narrow back seat, the Chicco KeyFit 30 Infant Car Seat and Base is one of the slimmest infant car seats on the market. At only 16.75 inches wide, it’s easy to get in and out of a tight back seat and to fit another child seat alongside it. 

This is an infant seat for newborns until your child is about 30 pounds. It’s compatible with Chicco strollers as part of a travel system. So it’s a reasonably priced option for your child’s first 12 to 18 months. However, as it is rear-facing only and reclined, you may find that your child outgrows it sooner than that. 

This means you’ll quickly be back in the market for a second-stage car seat. However, if you already have a toddler and need a car seat for a newborn that doesn’t take up too much space, the Chicco may be just the right thing for your family. 

Parents love that it’s lightweight, the base is secure and easy to use, and installation is easy. That’s important when you have your hands full! 

Material: Foam | Maximum Weight Recommendation: 30 pounds | Dimensions: 27.5 x 16.75 x 24 inches
View on Amazon | View on Walmart.com | View on Target.com

Best Budget Booster Seat: Century Boost On 2-in-1 Booster

Century Boost On 2-in-1 Booster
  • 2-in-1 BOOSTER SEAT: For big kids 40-120 lb, it transforms from highback to backless booster, because growing up happens
  • HAPPY PLANET COLLECTION: Fabrics made with recycled materials as part of our Do More promise to Recycle, Reimagine, and Give Back
  • SLIM AND LIGHTWEIGHT DESIGN: This space savior is easy to move from car to car
  • 6-POSITION, 1-HAND ADJUST HEADREST: Keep ’em comfy every step of the way
  • Budget-friendly
  • Lightweight and slim
  • Snack and cup holder
  • Covered in planet-friendly, recycled fabric
  • Only suitable for big kids, 40-120 pounds
  • Does not have a harness for younger toddlers—seat belt-only positioning

Suppose you’re looking for big kid seats for your toddler and older children. In that case, the Century Boost On 2-in-1 Booster is an excellent, budget-friendly option. 

This seat is only for kids who are ready for forward-facing, seat belt-only positioning. Its two modes are high back booster and backless booster. There’s no harness for younger toddlers who may still need one. 

However, the Century Boost On might be the right option if you’re carpooling with school-age kids, moving it from car to car, or need something lightweight for travel. 

It’s also nice to know that its fabrics are all made of recycled materials. So if you’re looking for a basic booster seat for your older children that’s slim enough to fit three across and easy to use, check out this great low-cost option. 

Material: ‎Polyester | Maximum Weight Recommendation: 120 pounds | Dimensions: 20 x 18.5 x 31 inches
View on Amazon | View on Walmart.com | View on CenturyBaby.com

Best Lightweight Car Seat: Cosco Finale DX 2-in-1 Booster Car Seat

Cosco Finale DX 2-in-1 Booster Car Seat
  • MAYBE THE LAST CAR SEAT YOU’LL EVER NEED The Cosco Kids Kids Finale DX 2-in-1 Booster Car Seat features two modes: forward-facing harness booster (30–65 lbs., 32″–49″, and at least 1 year old), and belt-positioning booster (40–100 lbs. and 43″–52″).
  • LIGHTWEIGHT AND CARPOOL-READY Perfect for families on the go, the Cosco Kids Finale DX is light and easy to move from car to car.
  • FITS 3 ACROSS THE BACK SEAT Narrow design fits 3 across the back seat of most vehicles for growing families with multiple kids in car seats at the same time.
  • EASY CLEAN-UP Removable seat pad is machine-washable and dryer-safe.
  • For kids from 30 to 100 pounds
  • Offers safety harness position and belt-positioned booster
  • Very lightweight, weighing only 11.5 pounds
  • Great budget price
  • Made in the USA
  • FAA approved for use on planes
  • Fits three across in many vehicles, but not all
  • Not very cushioned

If having a lightweight car seat that’s easy to move between cars or to travel with is a priority, the Cosco Finale DX 2-in-1 Booster Car Seat is an option to explore. This is among the lightest seats on this list. 

This is a big kid seat for toddlers and children starting at 30 pounds. The first mode, with a safety harness, is suitable for kids up to 65 pounds. For older kids up to 100 pounds, it can be used with a seat belt. 

If you need to buy additional car seats for multiple kids, the Cosco Finale is also very reasonably priced. However, some parents find that the trade-off for its affordability is a need for more cushioning and comfort that some more expensive brands may offer. 

In addition, at 18.25 inches in width, it is likely to fit three across in many cars, but not all. While it is narrow, there are definitely slimmer options on the market. Keep that in mind if you have a small car. 

Material: ‎Fabric | Maximum Weight Recommendation: 100 pounds | Dimensions: ‎18.25 x 19 x 29.75 inches
View on Amazon | View on Walmart.com | View on eBay.com

Best Car Seat for Travel System: UPPAbaby Mesa V2 Infant Car Seat

UPPAbaby Mesa V2 Infant Car Seat
  • PROTECTION FROM ALL SIDES: The adjustable headrest is reinforced with EPP foam to help absorb energy; our Side Impact Protection keeps baby’s head protected during a collision. The 4th rebound handle position allows for increased safety.
  • INSTALL IN SECONDS: We make installation quick and simple by combining our innovative SmartSecure system, auto-retracting LATCH design, red to green tightness indicator, and four-position adjustable foot. .
  • EUROPEAN ROUTING: Provides a safe and secure carrier-only installation when the use of a base isn’t convenient. The belt path easily secures the carrier at three points of contact to reduce movement.
  • FIRE RETARDANT FREE FABRICS: The Mesa V2 is made with fabrics that are fire retardant chemical free, including the large UPF 25 plus hideaway Canopy. It is also GREENGUARD Gold Certified to support healthier air quality and low chemical emissions.
  • Trusted brand
  • Fits with UPPAbaby Vista and Cruz strollers without adapters
  • Easy to use and install
  • Large canopy
  • Easily machine washable fabric
  • Slim 16.95-inch width, so it will fit in with other car seats
  • Expensive
  • For use with children only up to 35 pounds, so you’ll need to buy another car seat

If you’re looking for a slimmer car seat for your newborn to fit alongside one or two other car seats, the UPPAbaby Mesa V2 has a width of just under 17 inches. 

UPPAbaby is a trusted name in safe, well-tested baby products. In addition, parents report that the car seat is comfortable for infants and easy for parents to install. 

If you’re in the market for a car seat compatible with a stroller as part of a travel system, this Mesa V2 can go straight from car to either an UPPAbaby Vista or Cruz stroller without adapters; just click it in.

This is on the pricier side of infant car seats. Keep in mind that you will only be able to use it for a limited time before you need to track down a larger toddler seat. However, this may be a good infant option if your family is growing and you need space for everyone.    

Material: ‎Plastic | Maximum Weight Recommendation: 35 pounds | Dimensions: ‎27.5 x 16.95 x 24 inches
View on Amazon | View on PotteryBarnKids.com | View on UPPAbaby.com

Advantages of Using Slim Car Seats

How can you tell if a car seat is narrow or slim? Not all narrow car seats are advertised as “slim.” Generally, a car seat width between 16.75 and 18 inches is considered narrow. 

Average car seats usually have a width of 20 inches or more, so those few inches can really make a difference if you have a small car or if you’re trying to fit multiple car seats into a back seat. 

There are two main advantages to using slim or narrow car seats: 

You have multiple children.

Most regular cars can just about fit two car seats comfortably in the back seat. However, if you have more than two kids or you’re carpooling, slim car seats allow you to get three child safety seats in the back of your car safely and comfortably. 

You have a smaller car.

If you have a smaller car or a second car that’s small, a narrow car seat will be easier to use and maneuver in a smaller back seat. 

Three little boys, age-diverse brothers, travelling by car in safety seats, snacking and playing ball during the trip.

Criteria for Choosing the Best Slim Car Seat 

When you’re considering car seats, it’s easy to get distracted by the different features and designs. However, there are a few key things to remember to look for among all the bells and whistles. 

Factors to Consider 
Questions to Ask  
Number of children
  • Do you have two or more kids? Slim car seats are ideal for fitting everyone in the back seat and helpful for carpooling.
Ages of children 
  • How old are your kids and how far apart in age?
  • Are you passing an infant seat down to your newborn?
  • Are you buying a convertible car seat for your older child?
  • Does this car seat last from birth to ages 10-13?
  • How quickly will your kids outgrow it?
  • Will you have to buy a new car seat in about two years?
Size of car 
  • Do you have a smaller car? Slim car seats may be easier to fit in the back seat.
  • Will you be moving the car seat in and out of different cars?
  • Will you be using it for a lot of plane travel? If the answers are yes, try out the weight of the car seat before you buy. A lighter car seat will make life easier.
Ease of use 
  • How easy is it to buckle the seat into the car?
  • Does it need a separate base?
  • Will you secure it with the seat belts?
  • Is the cover removable and machine washable?
Compatibility with strollers 
  • Is it part of travel system?
  • Is it compatible with your stroller?
Comfort for child 
  • What kind of harness does it have?
  • Is it covered in breathable or ventilated fabric?
  • Does it have a cup holder?
  • Is it safe without feeling too constricting?
  • Are the fabrics used chemical and toxin free?

When you’re thinking about multiple kids in a back seat, you should also consider your own peace of mind and security, especially when you’re driving. 

For example, does not having a cup holder mean your child will drop their cup and nag you about it every two minutes? Is a narrow but uncomfortable seat going to lead to meltdowns when you’re driving? 

Managing multiple kids in a car when you’re driving can be stressful. However, your kids’ comfort is important because happy kids can get on with fun car activities and let you focus on the road.   


Are narrow car seats as safe as normal-sized car seats?

Car seats must comply with government safety standards, whether narrow or not. According to the American Academy of Pediatrics, the type of seat you choose depends on your child’s height, weight, and developmental needs. 

Make sure you do your research before you buy. Always read the manufacturer’s instructions for information on the safe installation and use of your car seat. 

Do child car seats expire?

Many new car seats now come with expiration dates that are generally between five and ten years from the manufacturing date of the seat. These expiration dates are meant to make parents aware of the age of the seat they are using and to look out for any degradation of the materials that may have occurred over time. 

Car seat technology and safety are also constantly evolving. Laws about car seats frequently change as well. The expiration date takes into account advances and changes that may be made during the lifetime of a car seat. 

A car seat expiration date is not the same as a date you might find on something like food, for example. It is there to help you judge the safety of the seat you’re using. 

You can register your car seat with the National Highway Traffic Safety Administration (NHTSA), which will inform you of any product recalls. They also have information about car seat inspection stations where you can go to make sure you’re using your car seat safely.

Best Slim & Narrow Car Seats

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