Can One Car Seat Do It All? What You Need to Know About All-in-One Seats
One car seat from newborn to big kid sounds great—but the reality is more nuanced. Here’s what to consider before you commit.
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Between infant car seats, convertibles and booster seats, most parents spend a lot of time—and a lot of money—on all things car seats for the better part of a decade. But is there a different way?
Meet the all-in-one car seat, a seat designed to grow with your child as they transition from a rear-facing seat to a forward-facing and eventually to a booster seat. As a Child Passenger Safety Technician (a CPST, someone who’s specially trained in car seat education and use), I always tell parents that all-in-one seats are usually not the only car seat you’ll ever need, but they can be a good choice for the right family—as long as you take the time to learn about their benefits and drawbacks.
Because each family has a different budget, we chose three top all-in-ones across different price points: the Graco SlimFit 3-in-1 Car Seat as the best affordable all-in-one, the Joie Saffron SI 4-in-1 Convertible Car Seat for a mid-priced pick and the Nuna EXEC Convertible Car Seat if you’re looking to splurge. We also selected a best rotating option and an all-in-one that works if you’re trying to fit multiple car seats across your back seat or drive a compact car.
Why Trust Babylist?
Babylist is the expert in baby; we know baby gear inside and out. We talk with parents face-to-face in our showroom and on our user panels and hear from thousands annually via our Best Baby Products online survey. We know what items millions of expecting parents are adding to their baby registries.
Firsthand professional and personal experience. I’m a CPST, which means I’m specially trained in car seat installation, usage, safety and education. I stay up-to-date on car seat education through continuing education classes, seminars and CPST education groups. I'm also Babylist's gear editor; I've been writing about baby gear at Babylist since 2019 and have been the gear editor since 2021. I’ve personally tested and reviewed dozens of car seats in this role, including many all-in-one car seats. And I’m the mom of two boys who are seven years apart, so I have over a decade of hands-on car seat experience.
Expert POV. I spoke to four additional CPSTs for this guide: Lainie Zedan, CPST-I, Child Passenger Safety Specialist at Safe in the Seat (the “I” in her title means she’s a certified instructor, too); Rebekah Kimminau, founder of The Baby Gear Consultant; Lani Harrison, founder of Lani's Car Seat; and Alli Cavasino, co-founder and CEO of JoyLet, a baby and kids' gear rental membership. They weighed in on the pros and cons of all-in-one car seats, how to install and use them properly and shared a few of their favorite options across different price points.
Car seat data. I regularly analyze which baby products our users are adding to their baby registries the most (and which ones they aren’t) and what our team of Merchandising experts—our buyers who are responsible for ensuring the Babylist Shop is stocked with the best and newest gear—is excited about. Studying this kind of data helped us choose which all-in-ones to narrow in on and which ones to recommend to new and expecting parents.
Feedback and reviews. I reviewed comments and feedback from Babylist’s annual product survey of thousands of parents, read customer reviews from hundreds of Babylist users and spoke to parents on our staff about their real-life car seat experiences.
How We Judged
Best Affordable All-in-One Car Seat
Pros
- Excellent value
- Slim profile
- Easy to install
- Good booster fit
Cons
- Poor newborn fit
- Some parents say the chest clip is too easy to unclip
- No backless booster mode
The price tag might be the first thing that catches your eye about this all-in-one car seat. “It’s a great deal,” one parent told us in our annual most-loved baby products survey. “It’s one of the best budget-friendly convertible seats that doesn’t skimp on features or safety.”
But beyond price, this seat has a lot going for it. While not the narrowest option, it is fairly slim, making it a good choice if you have a smaller back seat or have more than one child. The booster fit is good, which isn’t always the case with all-in-one car seats, and it’s easy to install.
“It’s not too bulky, [it’s] comfortable for baby, and super easy to use. I liked that it grows with them too,” another parent told us.
The main downside of this seat is newborn fit, which isn’t great. (This is a common con of many all-in-one seats and convertible car seats in general, and one of the reasons I recommend most parents start with an infant car seat then transition to a convertible once their child gets a bit older.) There’s no backless booster mode when your kid is ready for it. And some parents also report that the chest clip is too easy to unbuckle for precocious toddlers.
You’ll also want to pay close attention to the seat’s name. While it sounds similar, this seat is different from Graco’s LX model, the SlimFit3 LX 3-in-1 Car Seat, which we review later in this guide. The LX has similar all-in-one functionality as the SlimFit, but is over two inches narrower, a big difference in a smaller vehicle or when you’re trying to fit multiple car seats across your back seat.
Additional Specs
Seat Modes: Infant, convertible, high-back booster
Child Guidelines: Rear-facing: 5-40 lbs, head must be at least 1” below handle; forward-facing: 26.5-65 lbs, up to 49”; high-back booster: 40-100 lbs, 43-49”, min 4 yrs old
Best Mid-Range All-in-One Car Seat
Pros
- 4 modes of use
- Fits kids well in all modes (rear, forward and booster)
- Many safety and convenience features
- Sleek and stylish
Cons
- Bulky
- Cover is easy to remove and wash but not as easy to get back on
For a mid-priced all-in-one, the Joie Saffron SI is an excellent option. It packs a lot of value into its still-affordable price point, especially considering the seat’s lifespan.
Fit-wise, the Saffron SI works well for most kids, even newborns, making it one of the few all-in-ones I recommend if you plan on skipping an infant seat. Notable safety features include side-impact protection pods and removable side impact pads. There are plenty of adjustment options, including three recline options and a 10-position no-rethread harness, and a removable infant insert for the tiniest riders.
Features-wise, the seat shines, especially considering its price. It’s easy to use, with thoughtful touches you'd usually expect from pricier seats such as a magnetic chest clip, plush knit fabric, an integrated storage area to stow the harness straps once your child is ready for booster mode and a super-easy pull handle that transitions the seat from high-back to backless booster.
The Saffron is fairly wide and long front-to-back, so it may not work in more compact cars. And a few parents noted that while the cover was easy to remove and machine wash (just skip the dryer; it’s air-dry only), it was time-consuming to get back on.
Additional Specs
Seat Modes: Infant, convertible, high-back booster, backless booster
Child Guidelines: Rear-facing: 5-40 lbs, up to 43”; forward-facing with harness: 30-65 lbs, up to 49”; high-back booster: 40-110 lbs, up to 57”, min 4 yrs; backless booster: 40-120 lbs, up to 60”, min 4 yrs
Premium Pick
Nuna EXEC Convertible Car Seat - Caviar
From $680.00Pros
- Fits kids well in all modes (rear, forward and booster)
- Easy to install
- Compact front-to-back
- Legrest helps kids stay in position in booster mode
Cons
- Very expensive
- Wide when cup holders are in use
If you can swing the splurge, the Exec from Nuna is an excellent all-in-one choice. “It has a superior fit in virtually all modes,” notes Harrison, with the exception of tiny newborns (which is the case with most all-in-one seats). “It’s also easy to install and fairly compact.”
The Exec offers extended rear-facing and a leg rest for comfort. (Rear-facing is the safest way for children to ride; you should always max out your seat's rear-facing limit before making the switch to forward-facing.) There’s an anti-rebound panel to help absorb energy in the event of a crash and side impact protection pods. Comfort features include merino wool fabric (that’s also flame retardant-free) and two flip-out cup holders.
Harrison especially likes the seat’s leg rest in booster mode. “I find that it helps kids stay in position, especially when they first transition to a booster,” she notes. “It also helps support kids who sleep in the car.”
She also calls out the seat’s fit when it’s in booster mode, something that can be a challenge for many all-in-one seats. “The booster lap belt fit is excellent, and it doesn’t have armrests,” she explains. “Those things usually don’t go together. The lack of armrests isn’t a safety issue as long as the belt fits correctly, and it makes it much easier for the child to buckle.”
The big con of this seat is price—it’s steep. And like most all-in-one seats, almost all kids will outgrow it before their booster days are over, so you’ll need to purchase another high-back or backless booster when your child reaches the limits of this seat’s high-back mode.
Additional Specs
Seat Modes: Infant, convertible, high-back booster
Child Guidelines: Rear-facing: 5-50 lbs, up to 49”; forward-facing with harness: 30-65 lbs, 34-49”; high-back booster: 40-110 lbs, 43-57”, min 4 yrs
Best Rotating All-in-One Car Seat
Evenflo Revolve360 Extend All-in-One Rotational Car Seat with Quick Clean Cover - Revere Gray
From $329.99Pros
- Swivels 360 degrees for easy loading and unloading
- High rear-facing height and weight limits
- Anti-rebound bar
- Easy to clean
Cons
- Poor newborn fit
- Wide and long front-to-back
- Straps may twist easily
Rotating car seats have quickly become a parent favorite. I’ve been using one for the last few years and can’t imagine ever going back to a stationary seat. While rotation isn’t an essential feature for an all-in-one (there are minimal benefits to a booster seat that turns), it’s really useful in rear- and forward-facing mode. Evenflo’s line of revolving seats was praised by several of the CPSTs I spoke with due to their ease of installation and use, and the Revolve360 Extend is a particular favorite.
The seat works in three modes: rear-facing, forward-facing and high-back booster. The “extend” part in the seat’s name refers to its extended rear-facing limits (50 pounds), another big safety plus. It swivels 360 degrees and only needs to be installed once, unlike some other revolving seats that require you to uninstall and reinstall when switching from rear- to forward-facing. And there’s an anti-rebound panel for an extra layer of safety.
Unlike some of the other all-in-one seats on our list, the Revolve360 Extend does not have a backless booster option, so you’ll need to purchase one separately once your child outgrows the seat’s forward-facing harness mode. (While the seat technically works in booster mode for kids up to 120 pounds and 60 inches, almost all will outgrow it by shoulder height well before then. Plus, most older booster riders won’t be comfortable or confident in this type of high-back booster and will prefer a backless option.) This seat is wide and long, so it’s not a great choice for compact vehicles or three-across. And it doesn’t fit newborns well.
Additional Specs
Seat Modes: Infant, convertible, high-back booster
Child Guidelines: Rear-facing: 4-50 lbs, up to 48”; forward-facing with harness: 30-65 lbs, 28-49”; high-back booster: 40-120 lbs, 44-57”
Best Narrow All-in-One Car Seat
Graco SlimFit3 LX 3-in-1 Car Seat - Kunningham
From $209.99Pros
- Very narrow in all modes
- Fits 3-across in almost any configuration
Cons
- Very poor newborn fit
- Doesn’t recline as much as some other convertible seats
- Removable covers can be hard to get back on after washing
As a CPST, one of the most common problems I encounter is parents trying to fit multiple car-seat-aged kids across their back seat. A narrow seat solves this issue, and Graco’s SlimFit3 LX is a favorite slim option that also happens to be an all-in-one seat.
The SlimFit3 LX (not to be confused with the other SlimFit model we review above) is the narrowest convertible seat on the US market, including in booster mode. It’s a great choice if you have a smaller vehicle or need to go three-across in your back seat. It works in rear, forward and high-back booster modes and easy to adjust.
The most significant con is that this seat doesn’t fit younger babies well. “I usually don’t recommend it under six months,” says Harrison. (The booster fit is very good, however, which as we noted isn’t always the case with all-in-one seats.) And while the Rapid Remove cover is easy to take off, many parents say it’s tricky to get back on.
Additional Specs
Seat Modes: Infant, convertible, high-back booster
Child Guidelines: Rear-facing: 5-40 lbs, head must be at least 1” below handle; forward-facing with harness: 26.6-65 lbs, up to 49”; high-back booster: 40-120 lbs, 43-57”, min 4 yrs
What Is an All-in-One Car Seat?
An all-in-one car seat is a convertible car seat designed to work from the newborn days all the way through the big kid years. All-in-one seats transform from rear-facing seats to forward-facing ones, then ultimately to booster seats. Some convert to both high-back and backless boosters, while other models end up only as high-back booster seats. Most all-in-one seats boast a lifespan of about seven to 10 years.
All-in-One Car Seat Pros and Cons
All-in-one car seats do offer some benefits. They can reduce the number of car seats you’ll need to buy—and install—over time, and can be more eco-friendly. But there are some definite drawbacks that you should learn about before making your decision.
Pros of all-in-one car seats
Convenience. All-in-one car seats "eliminate the need to purchase multiple car seats as their child grows," explains Cavasino. They also remove the hassle of having to research, purchase and install a new car seat every few years.
Longevity. “Some all-in-one seats last longer than convertible car seats since they do have at least a high-back booster mode and sometimes a backless booster mode as well,” explains Zadan. Some even work from birth.
Environment. It’s much more eco-friendly to toss one car seat in a landfill than to throw away multiple seats over the course of your child's early years.
Cons of all-in-one car seats
False advertising. Almost all manufacturers advertise their all-in-one car seats as “the only car seat you’ll ever need.” Unfortunately, this simply isn’t true. While an all-in-one seat may last you longer than some convertibles, the reality is that many children will outgrow an all-in-one long before the seat’s stated limits either by shoulder height, because they feel squished or because they prefer a smaller, lower profile booster seat as they get older. Very few all-in-ones will take a child from birth until they’re seat belt-ready; most families will end up purchasing at least a backless booster or a high-back booster because the fit of their all-in-one isn’t cutting it as their child ages.
Correct use. Because these seats are described as all-in-one, many parents assume this is the only seat they’ll ever need—but that’s rarely the case. “In my experience, it leads to many parents having their six or seven-year-olds use only the vehicle seat belt since they have outgrown the seat that's supposed to be all-in-one,” explains Zadan. “They assume the kids are good now to go without a booster. But in reality, I have never even seen an eight-year-old who fits into the adult seat belt correctly without a booster.”
Poor newborn fit. In my experience, and according to the CPSTs we spoke to, most all-in-one seats don’t fit newborns very well. “The lowest harness height may be too high for a newborn, the recline might not be enough or the headrest may push the baby's head forward into an undesirable position,” says Zadan.
Portability and convenience. If you choose an all-in-one seat over an infant bucket seat, you lose both convenience and portability. "You won't be able to use your all-in-one car seat as a carrier or attach it to a stroller," explains Cavasino. Instead, you'll need to remove your baby every time plus bring a separate baby carrier or stroller along, which many parents find annoying.
Durability. "I find that many parents who buy all-in-one car seats do so for the convenience of only having to buy one seat. However, this doesn’t play out as anticipated for many families," says Cavasino. Ten years is a long time to keep any piece of baby gear, especially one that's likely to endure a lot of wear and tear and mess. There's changing safety technology to consider, especially over the course of a decade. And there's also aesthetics. "The beautiful pink seat that you pick out for your adorable baby girl will be very uncool when she’s five and has her own color preferences," adds Harrison.
There’s also cost to consider when thinking about purchasing an all-in-one car seat—and it can be both a pro and a con. If you’re shopping for high-end seats across the board, then an all-in-one may be more economical than purchasing three or four separate car seats over your child’s lifetime. But it’s also possible to get a very good convertible car seat + a combination high-back/backless booster for the same price as an all-in-one, and these two separate seats will likely offer a better fit along the way.
All-in-One Car Seat Safety
There are two safety considerations to think through if you're planning on using an all-in-one car seat: newborn fit and moving through a seat's modes (rear-facing, forward-facing, etc.) too quickly.
“[One of] the most common errors I have seen with all-in-one seats would be using a seat from birth when it does not fit newborns well," notes Zadan. If you're set on using an all-in-one seat from birth, be sure it's one with a good newborn fit.
"The biggest error I see is moving modes too quickly," adds Harrison. Because parents know their seat has a booster mode, they may be quick to make the switch before their child is ready. "Once a child starts complaining about the straps being too tight in forward-facing mode, for example, they may skip right to the booster instead of learning how to adjust the forward-facing seat," says Harrison.
You’ll also need to make sure you adjust the seat to the appropriate mode for the child’s age and size as they grow. Other common installation errors to look out for include:
Improper recline angles
Incorrect harness positioning
Incorrect use of lower anchors and/or seat belt
Tether (the top strap that anchors the top of a forward-facing car seat to your vehicle) not being used when appropriate in forward-facing mode or being attached to an incorrect anchor
