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Graco SlimFit vs Extend2fit Convertible Car Seat Comparison

There is so much more to a car seat than safety. You also have to consider comfort, convenience, whether you can install it properly, how big of a dent it will make in your budget, and so much more!

Note: Since this article was written, Graco introduced a newer version of the Slimfit, the Slimfit3 LX 3-in-1 that is 2″ narrower than the original Slimfit discussed in this article. See our Slimfit3 LX review here.

Two of the most popular and great across-the-board car seats we’ve reviewed are the Graco Slimfit and Extend2Fit car seats.

How do they compare? Here is your comprehensive comparison of the two.

Graco SlimFit 3 in 1 Convertible Car Seat | Infant to Toddler Car Seat, Saves Space in your Back Seat, Darcie

Graco Extend2Fit 3-in-1 Car Seat, Norah

Graco SlimFit vs Extend2fit

Perks of the SlimFit and Extend2fit Car Seats

Each of these convertible car seats has its benefits and drawbacks. Let’s talk about the benefits of each car seat now.

SlimFit is Lighter

The Extend2fit is not too heavy. You can carry it with one hand if you have a good grip on it. However, you cannot carry it with a child inside of it easily. But this seat does not have a carry handle on it to tote it this way anyway, as it is not an infant carrier. Some people do carry their sleeping child into their house inside the car seat, using two hands to do so, but the car seat’s weight plus the baby’s weight can be quite burdensome on a mother’s arms and back muscles.

The Graco Slimfit is a few pounds lighter. This makes it simpler to carry. However, it’s still pretty heavy for carrying long distances with one arm.

SlimFit Works for Longer

The next benefit is that the Graco Slimfit and the Extend2fit car seats both fit rear-facing and forward-facing.

However, the Graco Slimfit will fit your child for longer. Where the Graco Slimfit will fit your child until he is 100 pounds, the Extend2fit will only work for him until he is 65 pounds. This is a big difference.

Since many states require children to be in boosters until they are over 4 feet 9 inches tall, and since some children may reach 100 pounds or exceed it by this height, the Graco Slimfit truly will keep you from buying another car seat for longer.

One plus when it comes to the Extend2fit car seat is that it allows your child to sit rear-facing longer. The Graco Slimfit only allows your toddler to sit rear-facing until he is 40 pounds. However, your child can sit rear-facing until he is 50 pounds in the Extend2fit car seat!

One last thing that I believe is very important is the ability of each seat to fit a small baby. The minimum child weight of the Extend2fit car seat is 4 pounds. The minimum child weight of the Graco Slimfit is one pound heavier, at 5 pounds. 

Both Have Easy Adjustment

Graco Extend2Fit 3-in-1 Car Seat, Norah

One problem that many parents have with car seats is the need to rethread the straps each time their child outgrows the current settings. One benefit of each of these seats is that neither of them needs the straps rethreaded at any time. Both the Graco Slimfit and Extend2fit car seats are simple to adjust. Their harnesses and headrests merely slip upward with the push of a button, taking the harnesses with them.

SlimFit Takes Up Less Space

Do you have more than one car seat to fit into your car? This can be a problem with some car seats and can be a determining factor for many people when it comes to which car seat to purchase.

The Graco SlimFit car seat, being slimmer than most car seats, especially when the cupholders are folded in (which renders them unusable, by the way), can typically fit three seats across or two across with room for a passenger.

The Extend2fit is a little wider, so if you want to fit three across, you would need to have a much larger vehicle.

Equally Easy Installation

For those of us who have battled with trying to get an infant seat fitted into a base just right, you may be happy to know that neither the Graco SlimFit and Extend2fit car seats require a removable base. Their base is built right in!

There are reports of an issue with getting the seatbelt strapped in on the SlimFit car seat. It was reported that the opening was too small for the person to get their hand through. This can be easily fixed. The padding on the back of the seat lifts up. At that point, the seat belt can be pulled through the hole and pushed through the other side. Viola!

Graco SlimFit 3 in 1 Convertible Car Seat | Infant to Toddler Car Seat, Saves Space in your Back Seat, Darcie

Both car seats recline in four positions. These positions in both the forward- and rear-facing modes go a long way to keeping your baby or toddler comfortable during car rides, no matter how long they happen to be.

With the Graco SlimFit, when the seat is rear-facing, many mothers find it simpler to install it if they choose the incline position before they snug it down into the seat of the car. This is because it’s difficult to access the adjustment lever once it’s tightened down, as it’s hidden between the car seat and the seat of the vehicle.

Graco Extend2Fit 3-in-1 Car Seat, Norah

The Extend2fit has a level, which is easy to read. This makes it simple for those installing the car seat to know for certain whether the car seat is in the correct position or not.

Washable Cushions and Covers

Both the Graco SlimFit and the Extend2fit car seats are super easy to clean. If your child spills his drink on his car seat, it’s really not that big of a deal with these seats! Both seats disassemble for easy cleaning.

The SlimFit’s seat cover is washable and is easy to access. You don’t even have to remove the harness to do so!

The Extend2fit’s whole seat cushion is washable. The cushion comes off relatively easily.

The only problem with cleaning the cushion of the Extend2fit is that some people have found it very difficult to replace the cover. You see, there are small elastic loops at different places around the seat that hold it in place. These loops must be placed through tiny holes in the plastic frame of the car seat and then attached to a hook on the backside. This can be very difficult. However, there is a solution! Placing a crochet hook through the hole from the backside of the Extend2fit and then grabbing the loop and pulling it through the hole in this way makes fastening the cover to the car seat a breeze!

The buckles on both seats can be cleaned with a damp cloth, and you can spot clean the harness straps.

Both the Graco SlimFit and the Extend2Fit car seat is further made up of plastic and metal parts. These parts are easily cleaned. Merely use cool water and mild soap.

The SlimFit Seems Safer

When it comes to safety, both seats are engineered to go above and beyond, meeting or exceeding the standards set forth by the FMVSS 213. However, the Graco SlimFit seems to have an advantage in this area.

Neither car seat is dependant solely on the plastic with which they are made. Both frames are reinforced with steel. This provides durability and strength that makes them more dependable and safer. It also offers peace of mind to many mothers and fathers.

Both seats are Graco Protect Plus Engineered. This means that they went through rigorous testing to ensure the safety of your child. Graco used rigorous crash tests to check for the safety of these car seats in all four, side, rear, frontal, and rollover crashes.

The Graco Slimfit is also tested for side impacts. However, this is only for occupant retention and only with the seat’s 5-point harness in use.

When you live in a hot climate, the inside of your vehicle can get well above 120 degrees when parked. This can be a cause for concern when you think about your child’s plastic car seat sitting in that heat. However, both the Graco SlimFit and the Extend2fit car seats have undergone extra testing to assess the seats’ capabilities to withstand extreme temperatures.

The Graco SlimFit uses EPS foam for its cushion. I’m mentioning this because it truly is a remarkable safety feature. EPS foam does not allow for bacteria growth.

Drawbacks of the SlimFit and Extend2Fit

Each the Graco SlimFit and the Extend2fit have their drawbacks, but this is going to be true with any car seat that you look at.

Let’s look at each seat in detail. We are going to begin with the Extend2fit.

Difficult Adjustment on Extend2Fit

Though some say that the claim is unfounded, many say that the Extend2fit is difficult to tighten down for two reasons. Firstly, the strap that you pull to do the adjusting tends to be very stiff.

Secondly, there is only one adjusting strap, and it is only on one side of the seat, making it difficult to evenly tighten down the seat.

On the flip slide, the way that the adjustment strap is installed makes it difficult for the harness straps to get twisted.

Less-Than-Perfect Cupholders

The cupholders on the Extend2fit are square rather than being round. Many parents find it difficult to fit sippy cups into the cupholder due to this. If the cups do fit in, they do not seem to want to keep standing upright unless they fit snugly.

Graco SlimFit 3 in 1 Convertible Car Seat | Infant to Toddler Car Seat, Saves Space in your Back Seat, Darcie

The cupholders on the SlimFit fold in to make the seat thinner. Though this convenient if you need more room, it causes a problem. It renders the cupholders unusable.

Warning Label Issues

Both the Graco SlimFit and Extend2fit car seats have the warning labels on the front, center of the car seat where the baby, toddler, or child lays or sits. It hits their back.

There is a major problem with this. Because of the material that the warning label is made of, it draws heat. When the vehicle gets hot, so does the warning label on the car seat. If it gets very hot at all, it’s very uncomfortable or even painful for children to sit against.

There is a cure for this. Some parents place washcloths, towels, or icepacks over the warning sticker when they leave the car during the hot parts of the summer.

Hard to Adjust Harnesses

A few people have noted that, initially, the harness is difficult to adjust on both the Graco SlimFit and Extend2fit car seats. They do note that the harness on both seats get easier to adjust as the car seats get used. This, however, tends to be true to every car seat. 

The harness on the Extend2fit can be difficult to tighten when the car seat is rear-facing. The secret to this is to put your child in the car seat and to fully adjust it before installing it in your vehicle.

SlimFit is Sleeker

Though you can get the Extend2fit in nice colors, some people believe the appearance of this model to be mediocre at best. This is partially due to the color choices. This is also partially due to the fact that the straps can be easily seen on the back of the car seat.

The SlimFit, on the other hand, has pockets on the back of the seat to hold the straps.

A Note on Car Seat Safety

I wanted to include a section on car seat safety. This is basic information that should be followed regardless of which car seat you purchase.


When you place any car seat on the seat of the vehicle, you should have at least 80% of the base of the car seat on the seat of the vehicle.

When you install any car seat, you should get it tightened down so tightly to the seat that it should not be able to move frontwards, backward, or side-to-side. To get it tight enough, place your knee in the car seat as you tighten it down.

If you’re not sure exactly how to install your car seat, you can go to the police department when the Car Seat Technician is in, and they will install it for you and teach you how to install it properly yourself. If you purchase a Graco SlimFit or Extend2fit car seat, which is also manufactured by Graco, you can also call Graco Consumer Care to speak to one of their Certified Car Seat Technicians. The number there is 1-800-345-4109.

Harness Fit

When you put your baby or toddler into the car seat, there should not be much space between the harness and your child at all. In fact, there should only be enough room for you to comfortably get a finger in between the harness and your child.

Cold Weather and Proper Attire

It’s really very scary, but many parents just don’t know the consequences – never put your child into their car seat with a coat on! When your child is wearing a coat, you cannot get the harness tight enough. The padding of the coat will cause there to be too much give between your child and the harness. In that case, the harness will not adequately hold your child if you have a car accident.

Rather than putting your baby or toddler in the car seat with his coat on, warm your vehicle up before putting your child in the vehicle. Then, put a blanket over your child once he is buckled into the car seat to make sure he stays warm enough.

There is a coat made for wearing in a car seat. It is called the Buckle Me Baby Coat. You merely remove the front panel of the coat, buckle your baby in place, and reattach the panel via the side zip and velcro system.

Leaving the Car Seat

Children should not sit in a vehicle seat, using a seat belt alone until they are at least 4 feet 9 inches tall. They should be in the car seat until they reach the maximum weight and height. After that point, they should sit in a belt-positioning booster seat until they reach the 4 feet 9 inches tall.

Our Final Verdict 

Finally, the moment you’ve been waiting for. What do I think about the Graco SlimFit and Extend2fit car seats? Which one is best? Well, you’ve heard all the why’s and what for’s. Now for the final verdict.

My favorite is the Graco SlimFit. I have four children, two of whom are still in boosters. The SlimFit converts to a booster, whereas the Extend2fit does not go that far. If you purchase an Extend2fit, you’ll later need to purchase a booster seat for your child.

The SlimFit is thinner, offering more room in the backseat of the vehicle for another passenger between them. And, though it’s tight, if I need to, I can fit another thin seat in between them.

The Graco SlimFit’s cupholders fold in to create even more room if I need it. This is very convenient.

If my children have a drink to carry along with them, it fits so much nicer in the SlimFit’s cupholder than it does in the Extend2fit’s square cupholders.

The SlimFit also seems to have had more testing. According to the information that I found, this car seat, unlike the Extend2fit, has been tested for side impacts.

Since both the Graco SlimFit and Extend2fit car seats are typically identical in price on Amazon, there is no real competition in that respect. At this very moment, there is a $12.33 difference between the two with the Extend2fit being cheaper, but I’m not sure that $12.33 really outweighs all of the awesomeness of the Graco SlimFit.

Nishoni Harvey
Nishoni Harvey

Coming second only to God, mothering her four children and “wifing” are Nishoni’s true loves.

Writing pulls up close behind. Having written since she was just a little tyke, she has a file full of stories that she wrote as a first and second grader and beyond, which she hopes to turn into children’s books.
As of today, she has authored one novella, one novel, two non-fiction books, ghostwritten sixteen nonfiction books, written chapters in two other books, and published several articles, and blogs.