Graco Nautilus SnugLock LX Harness Booster Review – The Next Generation

2020 Graco Nautilus SnugLock LX/DLX Combination Seat Review

The Graco Nautilus has long been a go-to combination seat. Ever since its inception, the original Nautilus model has provided a tall harness for forward-facing kids, has served as a good booster for kids old and large enough not to need the harness anymore, typically fits kids and cars well, and is generally a reliable seat. It seemed like there wasn’t much that could make it better…until now.

Graco recently released the all-new Graco Nautilus SnugLock, which combines all the features we love about the original Nautilus with a SnugLock feature that cinches, locks and tightens the seatbelt for a less-complicated, secure installation.

To clarify, this is a forward-facing only carseat that can also be used as a highback booster and eventually as a backless booster. Graco refers to it as a “3-in-1” product which can be confusing because many consumers think a 3-in-1 carseat always means Rear-Facing/Forward-Facing/Booster. However, in this case, it means Forward-Facing/Highback Booster/Backless Booster. This is a Stage 3 carseat that is most appropriate for pre-school and school-aged children.

Let’s take a look at the specifications and features.

Nautilus SnugLock Weight and Height Limits:
  • Forward-facing with 5-point harness: 22-65 lbs., 27-49″ tall, at least 1 year old
  • Highback booster without harness: 40-100 lbs., 43-57″, at least 4 yrs old
  • Backless booster: 40-100 lbs., 43-57″, at least 4 yrs old
  • Backless booster with arms removed: 40-120 lbs., 43-57″, at least 4 years old


Nautilus SnugLock Overview:
  • 3 forward-facing seats in one (harness + highback booster + backless booster)
  • SnugLock feature for easy, secure installation with either LATCH or seatbelt
  • SnugLock feature acts as lockoff device when installing with seatbelt (so there is no need to also lock your seatbelt)
  • Removable armrests when in backless booster mode (gives older kids more hip room)
  • 6-position no-rethread harness
  • Energy-absorbing EPS foam
  • Premium push-on LATCH connectors
  • 4-position recline in harness mode
  • Steel-reinforced frame
  • 10-year lifespan before expiration
  • Built-in storage for the harness when using in booster mode
  • MSRP LX $219.99/DLX $249.99
Nautilus SnugLock Trim Levels:
  • LX models include all features listed above
  • DLX models include all features listed above plus enhanced soft goods, a RapidRemove™ cover which can be removed without uninstalling the seat, and an IIHS Best Bet Booster Rating in highback mode

  • Harness height range: 12″-18″
  • Maximum shoulder belt guide height: 20″
  • External widest point: 20″ at cup holders
  • Shoulder width: 12.5″
  • Hip width: 11.5″
  • Crotch strap depth: 6″, 8″
  • Seat depth: 13″
  • Seat weight: 21.7 lbs.
Installation/Fit to Car:

The original Nautilus 65 model tends to fit well in most vehicles, and the new Nautilus SnugLock is no exception. Even though it’s an entirely new platform, the shell of this new model is similar enough to the original that we don’t expect there will be many compatibility issues.

We installed the Nautilus SnugLock in booster mode and in harness mode with both LATCH and the seatbelt (separately–not at the same time) in a 2014 Honda Civic, a 2010 Honda Odyssey, a 2019 Honda Odyssey, and a 2016 Tesla Model X. The only possible issue I ran into was in the plus-one/eighth seat/jump seat in the center of the second row of the 2019 Odyssey. In that position, there was a bit of overhang on the side of the seat but the seat was still secure and it did not tilt to either side. Graco generally allows some overhang of the front of the seat in harness mode, but the manual does not address side overhang, so it’s unclear whether this would be considered an acceptable installation. (I did not install it in the plus-one seat of the 2010 model.)

The Nautilus has always been a pretty easy seat to install, and the addition of the SnugLock feature gives parents even more options. The SnugLock–whether you choose to use it or not–means that the belt path is nicely accessible and wide open, so it’s very easy to get the seatbelt or LATCH strap into position and also extremely easy to tighten it from different angles.

Graco did an excellent job designing this seat to make it easy to find and access the SnugLock panel. The cover has a clearly marked label indicating the location of the SnugLock, plus a fabric loop that just invites people to yank it. Once you do, you’ll find more clear markings on the lever used to open the panel. It’s all so intuitive, I don’t think anyone would have a hard time finding or accessing the feature.

Seatbelt installation: 

To install with the seatbelt, you open the SnugLock, then simply feed the seatbelt through the well-marked red opening on one side, through the SnugLock panel, out the red opening on the other side, and then buckle the belt. Then you’ll want to push down on the seat and remove the slack from the belt, but you don’t need to pull too hard–the SnugLock panel will tighten the belt as it closes. Then just close the panel! (If you have a hard time closing it, you might need to loosen the seatbelt just a tiny bit.) There’s no need to lock the seatbelt as the SnugLock serves as a lockoff.

Always make sure the seat moves less than 1″ at the belt path. If it’s too loose, open the panel and tighten the belt up just a bit and try again. (Also remember to attach and tighten the top tether.)

Here’s a video demonstrating how to install with the seatbelt and SnugLock:

The SnugLock feature is optional. If you don’t want to (or can’t) use the SnugLock panel for any reason (for example, if your vehicle has inflatable seatbelts, which can’t go into the panel), then you’d simply feed the seatbelt through the same red openings in the side of the seat, but you’d leave the SnugLock panel closed and bypass it altogether. If you don’t use the SnugLock with a seatbelt installation, you will need to make sure to lock your vehicle’s seatbelt, either at the retractor or in whatever way your belts lock. (Check your owner’s manual if you’re not sure.)

One installation issue that may arise in certain vehicles would be the issue of overhang in booster mode. When used in booster mode, the base of the Nautilus SnugLock must fit entirely on the vehicle seat (no overhang allowed). Thankfully, the base on this model isn’t particularly long so this shouldn’t be an issue in most vehicles, but it’s something to keep in mind if you have shallow vehicle seats in your backseat.

LATCH installation:

Installing with the “InRight” lower anchor connectors is also quite easy. The lower LATCH connectors on the Nautilus SnugLock are the deluxe push-on style which easily snap onto the vehicle’s anchors and remove with the push of a button.

When not in use, the LATCH strap stores in a handy (and, again, well marked) compartment toward the bottom of the back of the seat.

To use LATCH, simply open the panel, remove the strap, and then route it through the red belt path and into the SnugLock (as you would with the seatbelt). Make sure the larger portion of the connectors is facing up! Attach the connectors to your car’s lower anchors, push down on the seat, remove excess slack from the strap, and then close the SnugLock door. Check the seat to make sure it moves less than an inch at the belt path. If it moves too much, open the SnugLock, tighten the lower anchor strap some more, and try again. (And remember to connect the top tether!)

You can also bypass the SnugLock in LATCH mode if you’d like to.

LATCH Weight Limit: Please note that the child’s weight limit for using lower anchors is 45 lbs, so once a child is heavier than that, you’ll need to use the vehicle’s seatbelt to install the seat.

Center LATCH installations with Non-Standard Spacing:
Graco does not allow borrowing LATCH anchors from the outboard positions for use in the center with the InRight LATCH connectors.

Inflatable Seat Belts:
Graco has determined that the Nautilus SnugLock CAN be installed with inflatable seat belts found in some Ford Motor Company vehicles. When installing in harness mode, follow instructions for installing without the SnugLock lockoff panel. Other types of inflatable seat belts are still incompatible for use with the Nautilus.

Lockoff: The SnugLock acts as a lockoff, so there is no need to lock the belt if you use this feature. This is an excellent option for people with older cars without belts that lock, for people traveling abroad to countries whose vehicles typically do not feature belts that lock, or for caregivers who just don’t want to deal with the extra step.

LATCH in Booster Mode: The Nautilus SnugLock can use LATCH in booster mode as long as the vehicle allows it and as long as the lower anchors don’t interfere with the proper use of the seatbelt.

Fit to Child

The Nautilus typically does an excellent job fitting a wide range of kids. The 65-pound harness weight limit and 18″ top slots mean that it will accommodate most kids until they reach a reasonable booster age. The Nautilus SnugLock includes an insert that must be used if the child’s shoulders are below the bottom harness position. (If your child is still that small, please consider keeping them rear-facing.) The insert is optional beyond that, and probably not necessary for larger kids.

As a booster, the Nautilus also tends to position the seatbelt well on a variety of children. As with any booster, though, it’s important to examine the fit on each individual child in each seating position. (Booster seats should position the lap belt low on the hips, and the shoulder belt should cross the middle of the child’s shoulder.)

I tried the seat with my two youngest kids. Oliver is 7 years old and wears a size 6/7 shirt. Anna is 9 and wears a size 8.

Oliver normally rides in a booster seat, but he still fits in the Nautilus with the harness and has a bit of growing room left.

In highback booster mode, the seat fits both kids well. Anna is at the top booster position (with room to grow), but Oliver still has a couple clicks left.

I tried Anna in the regular backless mode, and that also worked well. The shoulder belt fit her fine, although there is a removable shoulder belt guide that should be used if necessary.

I also removed the armrests to see how that worked out.

Removing the armrests didn’t change the belt fit on her, and while it doesn’t decrease the outer dimensions of the seat at all, it does free up some space within the seat. You can see a comparison here:

Anna is very slim so the fit didn’t matter for her, but bigger kids might appreciate the extra hip room. Older kids might also like the sleeker look it gives. I like that Graco included cup holders and cubbies even in “armless” mode. They know what’s important to a kid!

***It is important to note that the armrests can be removed only in booster modes (highback or backless). The armrests must remain in place when used in harness mode. It is also worth noting that when the backless booster is used for a child weighing between 100-120 pounds, the armrests must be removed.***


My kids had no complaints about the comfort of the seat. The ample harness covers and buckle pads are a nice touch, and although my kids didn’t use the body support insert, that’s a nice option for smaller kids.

I tend to use my seats in the most upright mode, but the Nautilus does have four recline positions to give kids a little more comfort on long trips or to help the seat fit better in certain cars. (Note that the seat must be upright for booster mode.)

Although the armrests can be removed when the seat is used as a booster, my daughter said she preferred to keep them on because it was more comfortable for her. That preference will obviously vary by kid.

Ease of Use/Cover/Maintenance

It’s becoming more and more common for combination seats to come with easy harness-storage solutions so you can quickly put the seat into booster mode without having to remove the harness altogether. The Nautilus SnugLock is, thankfully, one of those seats.

Above the SnugLock compartment, there are two smaller doors for holding the chest clip and buckle tongues for easy storage when the harness isn’t needed. The buckle also tucks into a neat little compartment under the seat pad. (You will need to remove the harness pads and buckle pad and store those separately.)

Removing the back of the seat for backless booster mode is also quite easy. You just unhook the harness from the splitter plate in the back, then press a couple buttons to separate and remove the back portion. The splitter plate also stores neatly in a custom-shaped groove so it doesn’t flap around when the seat is being used as a booster.


As for general ease-of-use, the Nautilus SnugLock ranks up there as an easier one. It installs nicely in both LATCH and seatbelt modes, both with and without the SnugLock feature. The large opening used to access the SnugLock also provides an easy way to route the seatbelt/LATCH belt without scraping your hands and allows for easy tightening without having to do any weird contortions.

The no-rethread harness is easily adjusted by pressing a handle at the top of the seat and moving it up or down. Similarly, the recline on the bottom of the seat is smooth: Just pull the handle and tilt the seat back or forth–no wrangling necessary.

The harness adjuster (to tighten the straps) pulls easily and smoothly, so it shouldn’t be a struggle for people.

When it comes time to remove the armrests in backless mode, they simply pop off with the push of a button, and they snap back on just as easily.

The cover features little pockets for holding the harness out of the way for easy loading/unloading of the child. The chest clip pieces also tuck into the pockets, which sometimes are easier to fit in. I found it just as easy to tuck the harness behind the armrests instead, but it’s nice to give people the option in case the pockets work better for them.

The DLX version has a Rapid Remove cover that can be taken off without uninstalling the seat. The LX model I tested, though, has a regular cover. The cover isn’t the hardest I’ve ever removed, but it’s not the easiest, either. It mostly consists of well-contoured fabric with some snaps and tabs, which are nice, but there are a few thin elastic loops, which are the bane of my existence. I only counted six, though, and even those were easy to access, plus it was actually clear where they were supposed to hook. So all in all, not too bad.

The cover can be machine-washed on cold/delicate and should be drip-dried.

Other Information

FAA approval: The Nautilus SnugLock is approved for airline use when the seat is used with the harness. Like all booster seats, it is not approved for airline use when used without the harness (i.e., in booster mode).

When installing on an airplane (in harness mode, of course) you’ll likely need to bypass the SnugLock feature due to the placement of the seatbelt buckle.

Expiration: The Nautilus SnugLock has a lifespan of 10 years (in all modes) from the date of manufacture.

Crash replacement: The seat should be replaced after any crash.

Nautilus SnugLock Advantages
  • 3 modes of use: Forward-facing with harness, highback booster, backless booster
  • SnugLock lockoff and belt tensioner feature for easy and secure install
  • Deluxe push-on lower LATCH connectors (LATCH weight limit is 45 lbs.)
  • No-rethread harness with 6 height positions
  • Harness height & weight limits allow most children to use harness until they are ready to transition to booster mode
  • Fits a wide range of children in harness and booster modes
  • Easy-to-store harness in booster mode
  • Can use LATCH in highback booster mode
  • Removable armrests provide extra hip/leg room for older kids in booster mode
  • Rapid Remove cover available on DLX model
  • 10-year lifespan before expiration

(In fairness, these aren’t necessarily problems but I list them here to inform potential consumers of specific Nautilus SnugLock issues)

  • Requires some assembly before use
  • Heavy
  • Cover removal/reassembly can be a bit complicated on LX model
  • Made in China (though in fairness, so are many other quality carseats)

The all-new Graco Nautilus SnugLock LX/DLX lineup offers all the features we know and love about the original Nautilus models, then ups the ante with some extra ones. If you are in the market for a forward-facing combination seat, the Nautilus SnugLock LX or DLX is a solid, versatile choice and one of our 2019 Recommended Carseats and an Editors’ Pick from our experts. The SnugLock feature is great for helping parents get a solid installation quickly, and it also serves as a seatbelt lockoff so you don’t need to understand how the pre-crash locking features in your vehicle operate. Given the weight limits on the LATCH system for older kids (45 lbs. in this case), we feel the addition of a seatbelt lockoff for combination seats like the Nautilus SnugLock is a very important feature. The addition of the “armless” booster modes for bigger kids is also a nice touch, especially for parents who plan on getting long-term use out of the seat.

The Graco Nautilus SnugLock LX retails for $219.99 (often on sale under $200) and the Nautilus SnugLock DLX retails for $249.99.

Thank you to Graco Baby for providing a sample to review. CarseatBlog did not receive any compensation for this review, and all opinions are our own.


CarseatBlog Experts Rating

Editors’ Pick: Nautilus 65, Nautilus SnugLock


  1. Julie June 17, 2021
    • Kecia June 17, 2021
  2. Linda Prewitt October 21, 2020
    • Heather October 27, 2020
  3. Laura May 22, 2019
  4. Nicole L. May 5, 2019
    • SafeDad May 5, 2019
  5. Evelyn November 12, 2018
  6. Jenifer October 31, 2018
    • Jennie October 31, 2018
  7. Katrina Burgess October 30, 2018