Guest Blog: Graco Extend2Fit 3-in-1 and Milestone All-in-1 Comparison

Faceoff: How Do the Graco Extend2Fit 3-in-1 and Graco Milestone All-in-1 Compare in Terms of Features, Ease-of-Use, and Installation?

I recently purchased a Graco Extend2Fit 3-in-1 car seat. At 30 lbs, my 3.5 year old daughter hardly needs the 50 lb rear-facing weight limit, but she’s had a recent growth spurt in her legs and so I thought she might enjoy the option of the added legroom. Her current favorite seat is the Graco Milestone and so I was curious as to how these two 3-in-1 seats from Graco would compare.


The Graco Milestone (left) and Extend2Fit 3-in-1 (right) side-by-side in store at Babies R Us.

First, let’s define 3-in-1 in this situation, since there is no industry-wide accepted meaning. Both the Milestone and the Extend2Fit 3-in-1 car seats are able to be used rear-facing, forward-facing, and as highback belt-positioning boosters. Unlike the Graco 4Ever car seat or the Graco 4Ever Extend2Fit All-in-One, neither of these seats becomes a backless booster.

Both the Milestone and the Extend2Fit 3-in-1 car seats are rated to accommodate children from infancy to 100 lbs; however, a major difference is their rear-facing weight limits. The Milestone can be used rear-facing from 5-40 lbs, which is typical amongst current seats. Provided that they meet any height requirements, a 40 lb rear-facing limit will allow most children to rear-face until they are well into the preschool years. The Extend2Fit 3-in-1 car seat offers a 4-50 lb rear-facing weight limit, which is the highest available in the United States. Neither the Milestone nor the Extend2Fit 3-in-1 seat has a rear-facing standing height limit and so the only height limitation specifically for rear-facing is that the child have 1” of clearance between the top of the head and the red or gray headrest handle — which can be moved into any of ten positions. As a result, even tall children will be able to rear-face in either of these seats for a very long time. For heavier children, the 50 lb rear-facing weight limit on the Extend2Fit 3-in-1 means that even a boy in the 97th percentile for weight can rear-face past his 4th birthday.

These two seats have many similar features such as push-on lower anchor connectors, no re-thread harness, infant padding, removable harness pads, a convenient storage compartment for stowing the harness when the seat is in high-back booster mode, machine-washable soft goods, and Graco’s “roller bar” harness system on the back of the seats which allows the caregiver to tighten the harness quite smoothly. However, there are also some notable differences, which are summarized in the table below:

Milestone Extend2Fit 3-in-1
Ball-style level indicator with one rear-facing recline age range Bubble-style level indicator with two rear-facing recline age ranges (0+ and 3+ months)
Four recline positions: Two recline positions only for rear-facing, one only for forward-facing, and one for either forward-facing or belt-positioning booster Six recline positions: Three recline positions only for rear-facing, one for rear-facing or forward-facing, one only for forward-facing, and one for either forward-facing or belt-positioning booster
12” legroom when rear-facing 12 – 17” legroom (depending on the setting of the 5-position extension panel) when rear-facing
No specific feature for holding the harness back when loading/unloading; however, the loops on the harness straps prevent the buckle tongues from sliding all the way down “Fuss Free” buckle pockets for holding the harness out of the way when loading/unloading
Covered back Exposed back allows access to the harness straps
No special weight-specific rules for forward-facing Harness covers must be used if the seat is used forward-facing for a child under 25 lbs. Recline 6 must be used for a forward-facing child over 40 lbs.
One cupholder that can be moved to either side or removed to save space Two required cupholders

Rear-Facing Fit to Vehicle

Extend2Fit 3-in-1 in a 2010 Subaru Impreza

The true test of a seat that claims to be both compact and spacious is how (or whether) it will fit in a small vehicle. The Subaru Impreza represents the most compact vehicle in the Subaru line-up and competes with the Mazda 3, Honda Civic, Volkswagen Golf, and Hyundai Elantra. I was eager to see how it would handle the Extend2Fit 3-in-1.

Because of the slope of the seats, the Extend2Fit 3-in-1 could not be installed using setting 4, which is the most upright setting allowed for rear-facing. Without using a towel or noodle, there was no way to get it reclined enough to place the bubble level in the appropriate range. Setting 3 barely placed the bubble in the dark blue range, but I was able to move the passenger seat all the way back. There was barely enough clearance between the passenger and car seat seatbacks and the front seat had to be positioned quite upright, but when I sat in the front seat I was able to completely straighten my legs. I am 5’4” and this was far more legroom than I needed, but it was good to know that it was possible to have the front seat all the way back if necessary.


The Extend2Fit 3-in-1 car seat installed in the Impreza with the front passenger seat pushed all the way back.

Next, I moved the front seat forward and made adjustments until it was comfortable for me — I made it so that the recline was comfortable, the seatbelt fit well, and I still had a few inches between the glove compartment and my knees.

With this new passenger seat setting, I was able to recline the Extend2Fit all the way to the recline setting 1. With the slope of my vehicle seats, the bubble indicator was just barely in the light blue (0+ months) zone. It was a tight fit, but it would have been possible — just barely — to comfortably have a newborn in this seat while I sat in front.

The Extend2Fit 3-in-1 on the newborn setting in the Impreza. The front seat is adjusted comfortably for a 5'4" passenger.

The Extend2Fit 3-in-1 on the newborn setting in the Impreza. The front seat is adjusted comfortably for a 5’4″ passenger. The car seat is very close to the front passenger seat, but not touching.

But what about that legroom extension panel? Could I use it? I left the passenger seat on the “comfortable for me” setting, returned the seat to recline 3 (as upright as would work in my vehicle) and brought the extension panel out a click. It seemed like it would work, so I paused and thought “Oh . . . why not?” and pulled the extension panel all the way out to the most extended setting. When I set the Extend2Fit 3-in-1 back on the vehicle seat, the back of the shell brushed the front passenger seat, but the mark on the base indicated that well over 80% was still on the vehicle seat. After installing the car seat tightly, I was able to get enough clearance between the shell of the seat and the headrest of the passenger seat.

The Extend2Fit 3-in-1 seat in the Impreza with the extension panel fully extended.

The Extend2Fit 3-in-1 seat in the Impreza with the extension panel fully extended and the front seat adjusted to a comfortable position for a 5’4″ passenger.

The spacious Extend2Fit 3-in-1 in a small vehicle.

The spacious Extend2Fit 3-in-1 in a small vehicle.

I was shocked. I had thought I’d use the extension panel in the Forester and, maybe if I was lucky, I would be able to use the extension panel out a click in the Impreza. Instead, here I was with the leg rest fully extended and the headrest extended so high it nearly touched the ceiling — and I could still sit comfortably in front of it. Success!

Milestone in a 2010 Subaru Impreza

In the Impreza, the Milestone could fit on either of the two recline positions, but the difference between the two rear-facing recline settings was definitely noticeable. The Milestone fit most comfortably on recline 2 (less reclined); however, due to the slope of the seats I had to push hard on the back of the seat while tightening the LATCH strap in order to keep the ball indicator from leaving the blue rear-facing range. The ball indicator was barely fully-contained in the blue zone. The Milestone also fit on recline 1 and the level indicator stayed in the center of the rear-facing range when on this setting and so I would feel comfortable using it for a younger baby in this position. 

Extend2Fit in 2010 Subaru Forester

With the extension panel fully extended I could use the Extend2Fit 3-in-1 on either Recline 2 or Recline 3 and still fit up front as a passenger. With significant pushing on the back of the seat while pulling slack out of the seatbelt, I could also install it on Recline 4 and was just able to barely get the entire bubble into the dark blue recline range (appropriate for older children). When I retracted the extension panel and installed the seat on recline 1, I was able to install the seat at an appropriate newborn angle and still have plenty of room up front.


The Extend2Fit 3-in-1, reclined for a newborn, still leaves plenty of space in the Forester.

Milestone in a 2010 Subaru Forester

The Milestone has been Greta’s primary seat in our Forester for about nine months. We have had it on recline 1 (most reclined) for most of that time. In the beginning we had her seat on recline 2, but she fell asleep and had severe head slump and so I moved her back onto recline 1. The difference in vehicle fit between the two settings is quite minimal in the Forester. The Milestone has a ball level indicator with only one range for rear-facing and both recline 1 and recline 2 placed the ball within the acceptable range.

Fit to Child

Greta has always found the Milestone to be very comfortable. When she first got into the Extend2Fit 3-in-1, she noted that her legs touched the sides of the seat. I’m not sure whether the Milestone is actually wider, or if she just has gotten used to the lower sides. She only mentioned it the one time, though, and seemed otherwise comfortable in the Extend2Fit 3-in-1.

I had expected that she would be shocked and excited by the extra legroom — and I worried that she wouldn’t want to go back to her other seats without the extended legroom feature, but she didn’t even seem to notice the legroom when she got into the Extend2Fit 3-in-1. When she sat back in the Milestone she was just as comfortable as always. In fact, after about 3 weeks of Greta using the Extend2Fit 3-in-1 with the extension panel fully extended, I installed it in the most reclined setting for a newborn and stored the extension panel away in order to take some pictures and see how it fit in the Forester. Later in the afternoon I picked her up from preschool and she didn’t even notice that her Extend2Fit 3-in-1 had less legroom. At the time that I am writing this, she has been using it without the extension panel for three days and still hasn’t noticed. It’s a testament to the fact that young children really are quite flexible and they are more comfortable rear-facing than they appear to be when viewed from the eyes of an adult.

Greta sits in the Milestone and Extend2Fit 3-in-1 seats.

3.5 year old Greta sits tries out the Extend2Fit 3-in-1 seat. Her look of shock and excitement is not related to any aspect of the seat — just a goofy face she makes for photos.


Greta demonstrates one of the ways she likes to position her feet in the Milestone.


Greta lounges in the Milestone. Her legs are fully extended and resting up on the vehicle seat back.


Greta reclines in the Extend2Fit with the extension panel not in use.

I had been concerned about head slump when sleeping in the Extend2Fit 3-in-1 because reclines 3 and 4 are quite upright. She did fall asleep in the Extend2Fit 3-in-1 while on recline 3 in the Impreza about a week after we’d purchased the seat and she looked very comfortable and her head stayed within the protection of the headrest. She fell asleep a few times while using recline 4 in the Forester and her head slumped forward considerably some of the time and not at all at other times. This will certainly vary by vehicle and child.

One feature that Greta was excited about was the dual cupholders. She had been excited about the cupholder on her Milestone, but couldn’t really reach it when she was strapped in. She was strangely insistent on a seat with two cupholders but I suspected that this would just leave us with two out-of-reach storage compartments. I was pleased (and she was thrilled) to find that because of the more upright seat position she could more easily reach the cupholders in the Extend2Fit 3-in-1.

Forward-Facing and Booster Use

Even though my daughters are both still rear-facing and I had purchased these seats for their extended rear-facing capabilities, I tried Greta in the forward-facing and booster modes to get an idea of how the seat will accommodate her as she grows.

One important difference between the original Extend2Fit convertible and the Extend2Fit 3-in-1 is that they have different forward-facing rules. While the convertible version prohibits the use of harness covers when forward-facing, the 3-in-1 version has no such prohibition and in fact requires them up to 25 lbs when forward-facing. The original Extend2Fit convertible also requires recline 4 to be used for a forward-facing child weighing less than 40 lbs, while the Extend2Fit 3-in-1 does not. (The 3-in-1 does require that recline 6 be used for a forward-facing child weighing over 40 lbs.)

Both seats were easy to install and provided a great fit for Greta when she tried them out forward-facing. Her knees bent at the edge of the car seat and it looks like she will fit comfortably in both of these seats once she is no longer rear-facing. For now, she is puzzled by the concept of forward-facing and declared it “an unusual situation.”

Although she meets the 30 lb weight minimum, Greta is 6 months shy of being eligible to use these seats in booster mode. Nevertheless, since she is so close to the low end of the booster range, I checked out the belt fit on her. It was pretty awful. The shoulder belt could not be positioned in a comfortable way across her shoulder and the lap belt was up on her belly no matter how hard she tried to sit up straight. Since the booster fit was so terrible on both seats, I think it is less about the seat and more about the unsuitability of boosters for small and young children. I hope that these seats become usable booster options when my girls are older. The two seats were very similar in terms of their features when used in booster mode, and I did notice that the design of the Milestone shoulder belt guide was a little more intuitive for me to thread the belt than the Extend2Fit 3-in-1.  


Extend2Fit 3-in-1 belt guide.



Milestone belt guide.

To convert these seats into booster mode, you simply unsnap the back panels of the seat pad and tuck the parts into the little compartment at the back. The Milestone wins a point for ease of use in this step, since you can store all the parts without removing any of them. The Extend-2-Fit, unfortunately, involves removing the buckle instead of just moving it to the back position. There is a trade-off here, though: because the Extend2Fit does not need the compartment to be within reaching distance of the buckle, it is located at the back of the seat instead of the butt area. This means that crumbs and dirt are less likely to accumulate in the harness compartment.


The Milestone harness compartment (pictured above) is within reach of the buckle, making it easy to store all components without removing any of them. The Extend2Fit 3-in-1 storage compartment is about halfway up the back of the seat, making it less likely to accumulate debris, but also requiring that you remove the buckle in order to store it.

Ease of Installation

I found the installation of the Milestone with lower anchors very easy, in part because it is convenient to snake the tail of the LATCH strap under the armrest and get good leverage. You have to remove the cover a little bit, but it works. There is actually a mesh “window” in the cover right under the armrest and I wish it were just cut out entirely as this would make installation even easier. Installation with a seatbelt is similarly easy because of the large open belt path.


By simply unhooking one clip, it becomes very easy to get leverage when tightening the LATCH strap by pulling it up through the large space beneath the armrest.

The Extend2Fit 3-in-1 was more of a challenge to install because, with the extension panel pulled out, the belt path is farther away from the seat bight. Because I found it difficult to tighten the LATCH strap without snaking the tail up under the armrest like I did with the Milestone, I chose to install with a seatbelt.


On the Extend2Fit 3-in-1 you can get some extra leverage on the LATCH belt by working it up under the fabric cover, but the position of the cover and the difficulty in unhooking it from the seat means that the angle for pulling the strap isn’t right. I found it easier to use the seatbelt with this seat.

This also posed a difficulty in that the belt path is more difficult to access and felt smaller. There were some scraped knuckles involved. Because of the distance from the seat bight to the belt path, on more than one occasion I accidentally locked the belt (and started to let it retract) before I had intended to, which meant I had to start all over again.

The mechanism for reclining the car seats is different. The Milestone has the standard squeeze handle at the front of the seat where the child’s knees/feet go. The Extend2Fit has the extension panel mechanism in this area, so the recline is done via a handle on the base — under the seat area. Once you get used to it, it’s not a big deal. However, having the handle on the base means you need to use a second hand to control the seat’s movement and help lock it into the correct position. For those of us who are used to being able to squeeze the recline mechanism and push the seat with the same hand, it is awkward to squeeze the mechanism with one hand while pushing the seat into position with a second hand.

Ease of Loading/Unloading and Harnessing

In my experience, the Milestone definitely wins in terms of ease of loading. It is not only lower profile, but it also was less awkward for me to lift my daughter into the Milestone versus the Extend2Fit 3-in-1. With the Milestone I just lift her up, put her butt in the seat, and she maneuvers her legs into a comfortable position. With the Extend2Fit 3-in-1, because she didn’t have the back of the seat to push off of in order to get her butt in the right position, her legs would just sort of flop over the side and she and I would both struggle to get her butt and back fully situated in the seat. In a tight parking lot, where there isn’t much room to open the back door without hitting the car next to you, it is even worse. In one particular instance it was an exercise in acrobatics for both of us.

The harness is easy to adjust on both the Milestone and the Extend2Fit 3-in-1. I must say that I prefer the Milestone’s strap covers, which are shorter in the front than they are in the back — leaving a cutout for the chest clip to rest with some harness cover padding behind it. This places the chest clip the perfect position (at least on my children) and makes them very comfortable. My kids don’t use strap covers in most of their other seats, but the Milestone strap covers are a big hit.


The Extend2Fit 3-in-1 has “Fuss Free Harness Storage” which conveniently allows the parent to store the buckle tongues in little pockets at the side of the seat. Although this was one of the features that I thought I would love the most, I found that the buckle tongues tended to slide out of the pockets rather easily when loading or unloading the child. Overall, I felt like I was constantly digging the buckle tongues out from under my daughter and couldn’t figure out why I didn’t notice this issue with the Milestone. After using the seats interchangeably for awhile, I noticed that the Milestone had little loops sewn into the harness straps and that these prevented the buckle tongues from sliding all the way down to the base of the strap. The Extend2Fit 3-in-1 did not have these loops. It was a subtle difference, but it is enough to make a difference in how easy it is to load and harness the child.


Loops sewn onto the Milestone straps prevent the buckle tongues from sliding all the way down.


If the Fuss-Free buckle pockets on the Extend2Fit are not used (or the buckle tongues fall out), the buckle tongues slide all the way to the bottom of the harness strap. This can make it difficult to get them out from under the child.


These are both wonderful seats that are well-designed and pack many convenience features. For parents of large children, the Extend2Fit 3-in-1 is a great seat that allows even heavy and tall children to stay in the rear-facing position longer. The seat has some nice features such as the harness storage pockets, bubble level indicator, and the legroom extension panel. It is also exceptionally compact when used without the extension panel, especially for an older child who can sit more upright. In many ways, it is the most flexible seat I have experienced. If I were looking for a seat that I could reliably install in a variety of vehicles and be used for a variety of children, this is likely to be my first choice — especially if I wanted to keep the seat rear-facing and still be able to put in kids of various sizes.

For peanuts like my children (my 15-month old daughter pictured here), the Extend2Fit is definitely overkill!

My 15-month old daughter might enjoy extended rear-facing in this seat in the future, but for now the Extend2Fit 3-in-1 is definitely overkill!

That said, if I could personally only keep one of these seats, I would stick with my Graco Milestone. For average-sized children (mine included), the Milestone is perfectly capable of allowing rear-facing to an appropriate age. Furthermore, Greta did not note any increase in comfort with the extra legroom afforded by the Extend2Fit 3-in-1 and, in fact, seems to prefer the low profile of her Milestone. Finally, in terms of my own ease-of-use, I find the Milestone easier for loading, unloading, and installing. I don’t regret my decision to purchase the Extend2Fit 3-in-1 (especially since I have a younger child who might be pickier about legroom as she grows), but for an average-sized child I prefer the blend of features and value offered by the Milestone.

Post-Carsickness Cleaning Edit

Shortly after finishing writing this comparison, I had the unfortunate experience of my daughter getting carsick in the Extend2Fit 3-in-1. This necessitated removing the seat cover for cleaning and so I wanted to add some thoughts about the difficulty involved in this. There is no comparison between the Extend2Fit 3-in-1 and the Milestone when it comes to ease of cover removal/reattachment. The Extend2Fit 3-in-1 involves a great deal of fabric which must be tucked, elastic bands which must be threaded through tiny holes, and “button clips” which I found so difficult to remove I actually bent some of the plastic in the process. The Milestone’s cover, by contrast, boasts that it is “Quick Remove” and it does not lie. The Milestone definitely wins for ease of cover removal and re-attachment.


Guest Author Note: Arden is a middle school math teacher and a CPST. She lives in the midwest where she currently has two daughters and seven car seats.


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