Best 3 in 1 Car Seat – Top Five All-in-one and Booster Seats from 20+

If you want to know and plan to buy a 3 in 1 car seat, reading this ultimate guide is enough. Here in this article, we’ll discuss and explore a bit more details on 3-in-1 car seats and share some tips to choose a perfect 3-in-1 car seat to satisfy your child’s and your family’s needs.

3-in-1 car seats can be a car seat type, aka all-in-one; it can also be related to the modes, meaning you can use that 3 in 1 car seat in three modes, Graco Tranzitions, for instance. 

Here in this post, the majority of best 3 in 1 car seats are all-in-one, with very few portions being harnessed boosters with backless booster mode.

Each 3 in 1 car seat is recommended for meeting special needs, for example, a narrow profile to fit 3 across, rotatable for easy in and out, cheap price for budget-friendly families, etc. 

Before diving into the full review for every 3 in 1 car seat, you can have a quick view of the top five 3 in 1 car seats in this post.

Best 3 in 1 Car Seat

Best 3 in 1 Car Seats

Top Five 3 in 1 Car Seats

All-in-one

Graco SlimFit3 LX

$279.99

All-in-one

Safety 1st Grow and Go All-in-One Car Seat
Safety 1st Grow and Go

$179.99

All-in-one

Evenflo Gold Revolve360
Evenflo Revolve360

$399.99

All-in-one

Britax One4Life ClickTight All-In-One Car Seat
Britax One4Life

$399.99

Booster

Graco Tranzitions 2-in-1 Harness Booster
Graco Tranzitions

$139.99

Or, if you’d rather view the rotating car seats by weight and height limits, your budget, or by type (e.g. portable, fit 3 across, etc), click on either of the below.

By Weight Limit

See Our Top Picks Organized by Size Limits from 4 to 35 lb

By Height Limit

Best Choices Organized by Height Limits from up to 32 inches

By Price

See Car Seats Organized by Price (Prices Start under $200)

By Bonus

See Car Seats by Bonus features (e.g. for travel etc)

What Is a 3 in 1 Car Seat?

There are a ton of car seats on the market with the word 3-in-1 in their names. However, you may not get a direct answer for the real meaning of 3-in-1 as its name suggests. 

At first, a 3 in 1 car seat mainly refers to the all-in-one car seat that can be used into one of three stage options: rear-facing with a 5-point harness, forward-facing with a 5-point harness, and a booster seat. The idea of a 3-in-1 is to have one car seat that lasts as your child grows, from birth to tween.

Later, to extend the time for big kids in a booster, the manufacturer launched an interim car seat type – combination, a harness to booster in three modes: 5-point harness forward-facing, high-back booster, and no-back booster. 

The biggest difference between these kinds of 3 in 1 car seats lies in the direction. The former can be used in both rear-facing and forward-facing while the latter allows forward-facing only. You will also find the former kind will have a ‘convertible’ word in the name, while the latter should include ‘booster’.

Hope you have figured out these two kinds of 3-in-1 car seats. Maybe some examples will help you distinguish them. Move on reading our best 3 in 1 car seat recommendations.

Best 3 in 1 Car Seat to Fit 3 Across

Graco SlimFit LX 3-in-1 Car Seat

Graco SlimFit3 LX

Key Features
The Good
The Bad

$279.99

If you want a 3-in-1 car seat with a narrow profile to fit 3 across in the same row, you should look no further than the Graco SlimFit3 LX. It should be the narrowest 3-in-1 car seat on the market, thanks to its 16.7″ width.

As the name suggests, it is a 3 across car seat, and you can also know it seems to be an upgraded version. The very original version is named as SlimFit with a width of around 19.9 inches, which can save space somehow compared to those bulkier tanks like Britax One4Life, but not slim enough to do three across in most vehicles. The payoff is it’s a bit roomier for big kids. But this does not mean the SlimFit3 LX is not good for fitting big kids.

There are a lot of narrow car seats to fit 3 across, but why do we pick it as the best slim fit 3 in 1 car seat? So, what’s its secret? 

Well, there are several, including a 100 lbs/ 57″ big size limit, a 10-year lifespan, great safety features, and decent padding that delivers max comfort for the little passenger. 

Graco SlimFit3 X Fit 3 Across

This car seat is very slim, so it’s easy to install other seats around it if necessary, your family is still growing with two or more children, for example.

It has a 40-lb rear-facing weight limit, making it one of the best car seats for extended rear-facing. My niece still stays in her Graco SlimFit3 LX facing the back on her third birthday. The 100-pound weight limit and 57-inch height limit are commonly seen in the 3-in-1 car seats that last good years.

That matches their objective to go through three stages. So the SlimFit3 LX would be the last car seat you’ll need, from birth to the day when your child stops using a car seat.

One of the first things you’ll notice about the SlimFit3 LX is that the padding is removable and you don’t need to uninstall it to remove the cushion for washing and then reinstall it after getting the cushion on.

Thanks to the ‘Rapid Remove’ technology, you don’t need to struggle with that tough time when you need to wash the car seat cover. Also, the fabrics are machine washable, so you don’t hand wash it, saving time so that you’ll have more precious moments with your kids. 

However, it’s not as newborn-friendly as the infant car seats and other 3 in 1 car seats with an infant insert, even though it boasts of supporting a baby as low as 5 pounds. The SlimFit3 LX has a comparatively open design and might not fit well for small babies.

If you want to add a blanket or something to keep your baby stable, please contact the manufacturer first to make sure it’s okay to do that. On the other hand, SlimFit3 LX’s open design is good for toddlers. It is very cushiony and much more open, making the toddlers feel less strapped in the car seat. And they can climb it to sit well. 

Graco SlimFit3 Reclines

It’s tall. That’s the first impression you get when you look at the Graco SlimFit3 LX. That’s true, it’s 28.5 inches high. That means it may take a lot of room between the back seat and front seat if you install it flatly at the most reclined.

Luckily, it has four positions reclines so you can adjust to find a fitting angle without compromising your kid’s comfort and the space from the front passenger. That’s better than its competitor – the Diono Radian 3R – another slim 3-in-1 car seat to do three across. The latter does not have a recline at all and takes up a lot of space in the backseat, not so good in smaller vehicles. 

The Graco SlimFit series, including the SlimFit and SlimFit3 LX, have five colors for both boys and girls, with three colors for SlimFit and two colors for SlimFit3 LX. The Katrina-colored SlimFit3 LX is very suitable for girls and makes this 3 in 1 car seat list of the best purple car seats.

List of Other Narrow Profile 3 in 1 Car Seats

Slim 3-in-1 Car Seat Weight / Height Limits Width
Diono Radian 3R RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"
Diono Radian 3RX RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"
Diono Radian 3RXT RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"
Diono Radian 3QX RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"
Diono Radian 3QXT RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"
Diono Radian 3QXT+ RF:5-50 lb/ 44"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" 17.5"

Best Budget 3 in 1 Car Seat

Safety 1st Grow and Go All-in-One Car Seat

Safety 1st Grow and Go

Key Features
The Good
The Bad

$179.99

The Safety 1st Grow and Go is the cheapest 3 in 1 car seat in our database. A budget price under $200 is very uncommon among all-in-one car seats. Yes, the Grow and Go is capable of going through three car seat stages as well: rear-facing with 5 point harness, forward-facing with 5 point harness, and high-back booster.

From its robust build, good size limit, and thick padding that excellently accommodates a child from day 1 to 6-7 years old, the Grow and Go ticks every box that a family on a budget could ask for.

Combined with the necessary safety features that ensure your kid has a safe ride, lots of cushion for cozy, and improved all-around performance, it’s no surprise that the Grow and Go wins our award as the best 3 in 1 car seat under $200

Looking for a 3 in 1 car seat that’s tailor-made for growing kids, but that’s light on your wallet? Relax, your search is over. Supporting up to 100 lbs/ 52″ payload – and with a metal frame designed and built to meet the needs of a variety of kids – the Grow and Go is a no-brainer for families on a budget. 

It works great to fit babies, toddlers, and big toddlers. With a thickly padded insert, the Grow and Go is more friendly for newborns than the SlimFit3 LX, even though both have the same weight range in rear-facing mode: 5-40 lbs. Along with a 40-inch height limit, the Grow and Go car seat is one of the best car seats for tall babies. Your child could keep riding in rear-facing for at least 2 years old until they max out of the rear-facing weight or height limit.

The insert can be removed as your little one grows and can sit upright in the car seat. The maximum size limit for a 5-point harness in forward-facing is 65 lbs/ 49″. That’s very standard for most forward-facing car seats with 5 point harnesses. It’s a pity that the 52-inch booster height is 5-inch lower than other 3 in 1 car seats (52″ vs 57″) while the 100-lbs top weight remains as good as some all-in-one car seats.

We can say Graco SlimFit3 LX is the last 3 in 1 car seat you’ll need, but not true for Safety 1st Grow and Go. Why? The 52-inch is the reason. The child safety seat laws in most US states require that a child under 57″ (or 8 years old) should ride in a car seat or booster.

That means your child may max out the 52-inch booster height limit of this seat but they are still not as high as the minimum height requirement to stop using a car seat. But if you live or travel in a state that is not strict on this rule, for example, Alabama and Florida (6 yr), Arkansas and Nevada (6 yr/ 60 lbs), the Grow and Go should work well to the last minute until your child exceeds the limitations.

The Grow and Go does not come with any safety extras, but only a very basic level of protection, thanks to its metal frame and energy-absorbing foam. But it’s worth highlighting that this 3 in 1 car seat provides your child a cozy ride with plenty of padding, machine washable fabrics, and two removable cup holders. Considering its budget price, you can’t expect more for this 3 in 1 car seat!

Okay, a point earned the Grow and Go praise is the color options. There are 7 colors available for boys and girls. The Carbon Rose and Everest Pink are two good for girls. Both colors are nearly pink actually, making the Grow and Go have a position on the best pink car seats list. Some parents don’t think it is really pink, only the removable insert is bright pink.

That’s a common problem for all colored car seats including the purple car seats. The manufacturer won’t color the whole piece of the car seat pink or purple. It’s not economical for them to manufacture a seat cover and pad in a special color.

List of Cheap 3 in 1 Car Seats around $200

Cheap 3-in-1 Car Seat Weight / Height Limits Price
Evenflo EveryFit RF:4-40 lb/ 40"; FF: 22-65 lb/ 49"; Booster: 120 lb/ 57" $209.99
Graco TriRide RF:5-40 lb/ 49"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 57" $189.99
Graco SlimFit RF:5-40 lb/ 49"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 57" $219.99
Disney Baby Grow and Go RF:5-40 lb/ 40"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 52" $219.99
Century On Drive On RF:5-40 lb/ 49"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 57" $169.99

Best Rotating 3 in 1 Car Seat

Evenflo Gold Revolve360

Evenflo Revolve360

Key Features
The Good
The Bad

$399.99

If you want a rotatable 3 in 1 car seat, then the Evenflo Revolve360 is the best choice. It’s the most affordable rotating car seat that lasts a few years, making it a good option to grow with your child from day 1 to the day your child can stop using a car seat.

Like the Graco SlimFit3 LX, this 3 in 1 car seat would be the last one you’ll need for a child. It has an impressive size limit of up to 120 lbs/ 57″. That definitely fits big kids up to 8 years or older up to 10 years of age.

More than the 57″ height limit that will meet the car seat laws on a booster seat height requirement, the 120-pound top weight is unbeatable among all car seats on the market, making the Revovel360 a good 3 in 1 car seat for heavier kids. This is as good as Britax One4Life, only the 57-inch height limit is a bit lower than the 63-inch of the latter one. 

However, that’s not the exciting part of the Evenflo Revolve360. The most impressive feature of this 3 in 1 car seat is its 360 degrees of rotation, just as its name suggests. This rotatable design makes it easier to get your kid in and out of the car seat because you can spin it towards the vehicle door, without bending to reach your kids in a rear-facing car seat.

Plus, you can always swivel the car seat in 360-degree in any mode: rear-facing, forward-facing, or booster. That’s even better than some of the other swivel car seats with only 180 degrees. If you’re interested in a car seat that can spin 180 or 360 degrees, check our list of best rotating car seats.

Worry about the safety of this rotating 3 in 1 car seat? Don’t be. The Evenflo Revolve360 has passed the crash tests under the US federal safety standards, just like any other car seat on the market. It has two layers of SIP (side impact protection). Also, it comes with an anti-rebound bar, increasing the safety when you use it for babies in rear-facing mode. 

As for comfort, the Revolve360 performs top-notch. First, this rotating 3 in 1 car seat includes a no-rethread harness with 14 different positions and four recline options, allowing you to effortlessly find a perfect and comfy fitting position for a growing kid, no matter at 6 months or 8 years old. The Revolve360 has decent padding that is really plush and comfy.

With the included two cup holders for storing juices and snacks, I’m sure your kid won’t feel bored in the car seat even during long trips. Even if they fall asleep in the car seat, you don’t worry about your kid’s head falling forward. The headrest is very large and will hold your kid’s head for the best support. 

The down points? The Revolve360 rotating 3 in 1 car seat is bulky and heavy. That means it’s more difficult to move it from one car to another than moving the portable car seats. The car seat carrier IS detachable from the base, but the base is not purchasable separately. As a result, you probably will not use it between cars.

The rotating car seats are on the pricey side, even though the Evenflo Revolve360 is the most affordable. It’s priced almost $400 ($399.99), but you can get it with a discount on promotion sales like Black Friday.

Another reminder, the rotating 3 in 1 car seat can’t be completely rotated when it’s in rear-facing mode unless it’s in the fully reclined position. This does not conflict with the 360-degree rotation in all three stages because the seat still turns to the side-facing position. It’s not a big deal, but we want to mention it here to let you know about this point.

It’s bulky and large in size (you can know this from its image or the first time you unbox it). If Britax One4Life is a one-piece tank, this 3 in 1 car seat would be a huge tank consisting of two parts (the base and the car seat). Measuring 19.8 x 25.9 x 21.0, the Revolve360 takes a bit more space in the back seat, so probably isn’t ideal for small cars or sedans. 

As a rotating 3 in 1 car seat, the Revolve 360 boasts of its minimum weight limit as low as 5 pounds, however, car seat experts note that it’s tricky to get a good fit with a newborn or smaller baby in it, even though it includes cushioned infant insert to try to provide a stable fit for newborns.

Ultimately, if you’re looking for a long lasting, rotating 3 in 1 car seat that packs a punch and is also capable of carrying a kid up to 120 pounds, then the Evenflo Revolve360 is for you. The combination of its steel-reinforced metal frame, plushy and comfy padding and 360-degree rotation for most convenience make it one of the most exciting and maneuverable 3 in 1 car seats.

Last but not least, the Revolve360 is made for boys and girls, by providing obvious different colored seat covers. If you have a girl, Oral Pink should be the best choice. If you’re interested in a car seat with pink color, check out our guide on the best pink car seats.

List of Other Rotating 3 in 1 Car Seats

Rotating 3-in-1 Car Seat Weight / Height Limits Price
Graco Turn2Me RF:5-40 lb/ 49"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 57" $449.99
Maxi Cosi Emme RF:5-40 lb/ 40"; FF: 22-65 lb/ 49"; Booster: 100 lb/ 52" $449.99

Easy to Install 3 in 1 Car Seat

Britax One4Life ClickTight All-In-One Car Seat

Britax One4Life - 120 lbs

Key Features
The Good
The Bad

$399.99

The holy grail of heavy-duty 3 in 1 car seats for taller and bigger babies and kids, the Britax One4Life can support a load of up to 120 lbs until your child reaches 63-inch top height. Yep, you read that right – 120 lbs/ 63″. But the higher size limit is not the only impressive feature the One4Life has in its locker.

Thanks to the easy-to-use ClickTight technology in its pad, the One4Life boasts a (frankly outstanding) ultra-easy seconds-installation with the seat belt. Packed with premium features – yet designed for practically – it’s an all-rounder 3 in 1 car seat that you can count on.

The One4Life is very suitable for taller babies and kids. The 120 lbs/ 63″ booster seat limit is one reason. It’s very common to see a few 3 in 1 car seats with a 120-pound weight limit, but the 63-inch height limit is rare.

Only Britax has this highest height limit in its all-in-one car seats and booster seats. This is very friendly for taller kids if you live or travel in a US state that emphasizes the minimum age requirement (usually 8 years old) to stop using a car seat, for example, Illinois, Indiana, Nebraska, etc.

Britax One4Life Install in Vehicle

This 3 in 1 car seat is the only one on this list with a rear-facing weight limit of up to 50 pounds. This is very seldom seen in the car seat world; only a few models like the Graco Extend2Fit (convertible), Diono Radian 3R (3 in 1), and Baby Jogger City Turn (another rotating 3 in 1) in our database have this 50-lb rear-facing limitation.

Along with the 49″ height limit that is the same as the forward-facing 5-point harness, the One4Life is capable of having a toddler up to 3 years old in rear-facing, making it a good 3 in 1 car seat for taller babies if you’re a parent who wants to keep kids rear-facing for a longer time. That’s easy to understand, rear-facing is considered safer than forward-facing.

While Evenflo Revolve360 is good for its convenience to get a kid in and out of the car seat, the Britax One4Life should be well-known for its ease to install the car seat. The company’s patented technique – ClickTight, allows you to install it in seconds with the seat belt. 

As a matter of fact, this installation technique is also a game changer. Typically, parents would choose the LATCH system (this 3 in 1 car seat features as well) because this method is much easier and you just need to attach the LATCH connectors to the lower anchors in the seat.

It’s true that adjusting the seat belt for a tight installation takes longer time and more patience. Now, ClickTight makes it easier to achieve a tight and proper installation with the seat belt.

Also, installation with the seat belt won’t reduce the weight limit so you can keep the current stage for as long as possible until the kids max out the 5-point harness height or weight limit (50 lbs/49″ for rear-facing and 65 lbs/ 49″ for forward-facing), while LATCH installation has a lower weight limit than the car seat’s 5 point harness weight limit.

Britax One4Life ClickTight

A few other features that are worth highlighting about this 3 in 1 seat include a no-rethread harness with 15 different positions, nine recline options, a SafeCell crumple zone, a V-shape tether, a removable body pillow, an infant insert, plenty of padding for max comfort, several easy-to-use features to ensure you’re getting a safe, secure install and machine washable fabrics.

And most important, two cup holders are included. This would make you feel it’s worth the price; after all, the $300+ convertible car seats from the same company like the Advocate, Boulevard, and Marathon don’t have a cup holder. But we do recommend you get a car seat with cup holders because toddlers would want to enjoy themselves in their space.

You won’t want to take it for air travel because it’s a heavy tank, weighing up to 30 pounds, notwithstanding the approval by FAA for airplane use. It’s also one of the bulkiest car seats, so probably isn’t ideal for smaller cars or sedans.

3-in-1 Booster Car Seat with 5 Point Harness

Graco Tranzitions 2-in-1 Harness Booster

Graco Tranzitions

Key Features
The Good
The Bad

$109.99

The last, but definitely not least, 3 in 1 car seat on our list is Graco’s Tranzitions. Unlike the other 3 in 1 car seats that go through 3 car seat stages on our list, the 3 in 1 here is 3 modes and works only when the seat is in forward-facing mode – but the Tranzitions is still good to ride a toddler 1 year or older for a few years.

The minimum weight requirement for this car seat is as low as 22 pounds. That means, it can be used for an infant around 1 year old for forward-facing. However, the best recommendation is to keep your child as long as possible until they max out the infant car seat’s top weight or height around 35 lbs/ 32″, which typically happens around 18 months.

If it’s legal to turn a 1 year old child forward-facing in your state, it’s okay to use the Graco Tranzitions. But if the local laws require a child passenger to ride in rear-facing mode until the second birthday, like the California and New York, it’s better to use a convertible car seat for extended rear-facing and then transition to forward-facing.

Better than most harnessed boosters with two modes – 5 point harness forward-facing and high-back booster, this 3 in 1 booster seat has an extra backless mode, helping save your money. You don’t need to buy another backless booster seat for big kids around 6~7 years old.

After turning into the backless mode, it’s low-profile and child-friendly for your kid to climb in and out, better than the backless mode of Graco 4Ever DLX. The latter is a bit higher than a traditional no-back booster.

The fabric on this 3 in 1 car seat is lightweight while the frame is made of plastic. As a result, the Graco Tranzitions 3 in 1 car seat weighs just 14.97 pounds, very near to the weight boundary to be a lightweight convertible car seat. It’s a pity that this car seat does not support rear-facing mode.

The forward-facing and booster weight limits are on the higher side for a 3 in 1 car seat, so you’ll be able to use this seat for quite a while, and there’s an 8-position headrest adjustment position for extra comfort. There is no base under the seat pad for adjusting the recline positions. The payoff is that this 3 in 1 car seat has a really low profile for big toddlers to climb in and out by themselves, no matter which mode you’re using.

A few other things worth calling out are the seat’s energy-absorbing foam, compact but solid armrest, and fairly affordable price. Priced a bit over $100, it’s one of our best cheap car seats under $200 in the 60+ car seat database. It’s also one of the narrow 3 in 1 car seats which is good to note if you’re trying to save space in your back seat. However, the 19-inch width is not that ideal for fitting 3 across if you have multiple children in a car seat.

Best 3 in 1 Car Seats by Performance

Weight/ Height Limits 3 in 1 Car Seat Price Type
100 lbs/ 52" Safety 1st Grow and Go $179.99 All in one
100 lbs/ 57" Graco SlimFit3 LX $279.99 All-in-one
100 lbs/ 57" Graco Tranzitions $139.99 Booster
120 lbs/ 57" Evenflo Revolve360 $399.99 All-in-one
120 lbs/ 63" Britax One4Life $399.99 All-in-one

Best 3 in 1 Car Seats by Price

Rank Price 3 in 1 Car Seat Weight/ Height Limits Type
1 $139.99 Graco Tranzitions 100 lbs/ 57" Booster
2 $179.99 Safety 1st Grow and Go 100 lbs/ 52" All in one
3 $279.99 Graco SlimFit3 LX 100 lbs/ 57" All-in-one
4 $339.99 Evenflo Revolve 120 lbs/ 57" All-in-one
5 $399.99 Britax One4Life 120 lbs/ 63" All-in-one

Best 3 in 1 Car Seats by Bonus

All these best 3 in 1car seats are good options for optimal protection. Some of them may have bonus features to satisfy different needs. Check below. 

Cheap:

Lightweight

 

Slim Fit to Do 3 Across

Rotating

How to Choose the Best 3 in 1 Car Seat for Toddlers

It can be extremely difficult to whittle down the choices when you’re looking for the best 3 in 1 car seat to grow with your child. After all, every family’s needs are different! Here are some key features to look for as you consider your options for a multi-stage lasting 3 in 1 car seat:

What is the safest 3 in 1 car seat for kids?

One of the most important features of a toddler 3-in-1 car seat is safety. Why? Because you’ll need it to work normally for optimal protection of your little one in case of a crash. 

But you don’t need to worry about the safety of a 3 in 1 car seat, because all child restraints sold in the US are required to comply with the testing requirements of FMVSS No.213 on child restraint systems.

Also, if the car seat has a 5-point harness, it should have side impact protection. That’s also the requirement by the government for car seats with a 5-point harness.

So all the 3 in 1 car seats can be used for safe rides to your child as long as you can use them correctly following the manufacturer’s instructions. It’s just that some car seats come with safety extras.

For example, Graco SlimFit3 LX features a ProtectPlus technique for enhancing protection from all-around. Britax One4Life uses SafeCell technology to reduce the crash energy and impact.

However, even the cheapest Safety First Grow and Go is a safe 3 in 1 car seat for use. 

Another difference in the frame material catches parents’ eyes and makes them think the car seat has a different safety rating – metal or plastic. It’s true that metal frame-made car seats will last longer than plastic frame-made car seats. But this does not mean the plastic-frame car seat is less protective.

The right size 3 in 1 car seat

We usually think that “smaller is better” when it comes to a car seat, but in the case of 3 in 1 car seat, it’s more about the right size for your situation and your child. What should you consider?

A car seat’s “shell height” refers to how much space there is along your child’s back and head. For kids who are rear-facing, they should have at least one-inch of shell above their heads in addition to being within the car seat’s advertised height limit. (not applied to Graco Tranzitions because it’s forward-facing only.)

After you switch the 3 in 1 car seat to forward-facing you’ll need to make sure that the tops of your child’s ears are still within the shell and that the top harness slots are above your child’s shoulders. 

You may not need to get the tallest possible car seat (like Britax One4Life) unless your kid is ultra-tall than his or her peers. By the same token, slim-fit car seats could be unnecessary for a family with one or two kids, only if they are planning to have a third baby.

There’s truly no ideal size, just what suits you best. A car seat with a narrow profile will generally fit better in cramped spaces like small cars. A car seat with a rotating design may be bulkier but friendlier for parents and grandparents to wrangle the kids in and out.

An easy to install 3 in 1 car seat

When you’re using a car seat, one thing for sure: you’re very likely to have to install it more than one time, especially if you have a traditional 3-in-1 car seat with both rear-facing and forward-facing modes. Swivel car seats are an exception.

What can make or break a 3 in 1 car seat’s ease of installation? There are a few things to look for.

All American car seats, including a 3 in 1 car seat, can be installed with either the LATCH systems (most up to a certain weight) or a seat belt. The actual installation may vary a bit, however.

LATCH systems are the first choice for most parents because it’s simpler to connect them to the seat’s lower anchors in the car. But Britax changes the game. It released a technology called ClickTight that makes installation with the seat belt easier than the LATCH. Can’t believe it, right? But it’s true – you’ll get a tighter and more proper car seat installation with the seatbelt. Another fact about the Britax car seats with this technique is that they are more expensive, over $300.

Another game changer in the car seat installation is the rotating car seats. Unlike other traditional 3 in 1 car seats that need to be installed at least twice, one for rear-facing and the other for forward-facing after turning the car seat around, the swivel car seats need just one-time installation. Then you can spin it 180 degrees or 360 degrees to turn the car seat rear-facing or forward-facing.

A comfortable 3-in-1 car seat

This last factor for choosing a 3 in 1 car seat is perhaps the most subjective. But the last thing you want is a cranky kid on a long-trips in the car!

Some car seats, especially those cheap travel car seats, have virtually no padding over the plastic shell. If you’re just using the car seat on the plane and then for a quick taxi ride, it won’t matter too much. But if you plan to use that seat every day for pickup, you won’t want your baby in this type of car seat anyway.

Luckily, all the 3 in 1 car seats are thickly padded and they are comfortable to use. Even the lightest Graco Tranzitions 3 in 1 car seat looks plush and cozy with decent padding. Otherwise, it won’t be one of the most popular toddler car seats on Amazon.

3-in-1 car seat vs 4-in-1 vs all-in-one

Okay, coming to the most complicated part. 

Let’s start with the simplest: all-in-one (RF, FF, Booster). It’s easy to understand because this type of car seat will go through three stages: rear-facing, forward-facing, and booster, please refer to the car seat stage definition from NHTSA.

If you notice a car seat states in the product description or specs that it has rear-facing, forward-facing, and booster, then it should be an all-in-one car seat. This type of car seat can be used for a few years so as to grow with your child.

4 in 1 car seats (RF, FF, High-back Booster, Backless Booster) are included in the all-in-one car seat type. Some of the  4 in 1 car seats divide the rear-facing stage to infant and toddlers; we call this a fake 4 in 1, as 99 percent of all-in-one car seats have an extendable weight limit up to 40 or 50 lbs and are good for infants and toddlers to stay rear-facing longer. Other real 4 in 1 car seats have an extra mode – a backless booster. That means you can remove the back support and use it as a conventional no-back booster.

At first, the 3 in 1 car seat is the same as the all-in-one and last three car seat stages. This concept is easy to understand when compared to the 4-in-1 car seat. 

However, to satisfy the needs of parents who want a toddler car seat after the infant car seat, the manufacturers launched a type to fill the gap – Combination, which is a booster seat with 5 point harness and can be used forward-facing only. In this way, the booster seat can be extended for forward-facing use in the 5-point harness. Most combination car seats include two modes – a 5-point harness forward-facing and a high-back booster. If a combination car seat has the third mode – backless booster. (just like 4 in 1 car seat), then it is considered a 3 in 1 car seat.

So a 3 in 1 car seat can be an all-in-one or a combination car seat. The only way to distinguish them is to confirm if the 3 in 1 car seat has a rear-facing size limit (usually weight limit) or not. If it has a rear-facing limitation, it should be an all-in-one; otherwise, it probably belongs to a combination car seat.

FAQs on 3 in 1 Car Seats

How does a 3-in-1 car seat work?

A 3 in 1 car seat offers three modes to use. If it is an all-in-one, it should “do it all” and will go from infant seat to booster: rear-facing, forward-facing, and high-back booster.

If it is a combination car seat, then it can be used forward-facing only, not so ideal for newborns and small infants, but still good for toddlers to big kids: forward-facing, high-back booster, and backless booster.

What is the difference between 4-in-1 and 3-in-1 car seats?

To keep it simple, a 3-in-1 car seat goes from infant to booster seat: rear-facing, forward-facing, and high-back booster. And a 4-in-1 car seat also goes from infant to booster, but includes one more step: rear-facing, forward-facing, high-back, and backless booster.

If you consider a combination with a backless mode a 3 in 1, things can be easy as well because it lacks only the rear-facing: forward-facing, high-back, and backless booster.

How long is a 3 in 1 car seat good for?

All the 3 in 1 car seats on this list can be used safely only for a defined period of time, typically 7 to 10 years. The actual usable time starts from the day you purchase. It should be shorter than the given lifespan, which started from the date of manufacture. 

3 in 1 car seats in the all-in-one type last longer, reaching 10 years. On the other hand, the 3 in 1 car seats in combination type probably have a 7-year usable life, like the Graco Tranzitions.

What is the safest 3-in-1 car seat?

All the 3 in 1 car seats on this list are safe to use. They all meet the federal safety standards and have side impact protection.

What is the best 3-in-1 car seat for newborn?

On this list, all the 3 in 1 car seats that allow rear-facing are good for newborn. They all have unique features and may fit different needs.

Graco SlimFit3 LX – a narrow profile 3 in 1 car seat to fit 3 across. But it’s an open design and does not have a thick-cushioned infant insert for a good fit for newborns.

Safety 1st Grow and Go – a cheap 3 in 1 car seat for newborn

Evenflo Revolve360 – a rotating 3 in 1 car seat for newborns to get in and out easier. This would be best if you want to put newborns in a bassinet or stroller.

Britax One4Life – an easy-to-install 3 in 1 car seat for newborn

How do you convert a 3-in-1 car seat to a booster?