Chicco OneFit Multimode Car Seat Review

Chicco OneFit installed forward facing with lower anchors and top tethers

We find ourselves quite fond of almost everything Chicco makes, including rear facing only car seats, convertible, multimode, and booster seats. That doesn’t mean we’re biased, it means that Chicco consistently develops some pretty awesome car seats. The OneFit is a multimode seat that has the same high level of quality we have come to expect from Chicco. The seat combines many ease of use features with a long lasting harness and booster mode.

Chicco OneFit ClearTex fabric label

The OneFit is very similar to the Fit4 in nearly every way. The major difference is the Fit4 has a multistage bum insert system and the OneFit has one bum insert. Both have the same awesome harness height and booster guide height.

Looking at the NextFit compared to this seat, the OneFit is entirely different from the Nextfit. The Nextfit does not convert to booster mode and has a significantly lower maximum harness height.

The OneFit’s soft goods have ClearTex fabric. This type of fabric passes the Federal Motor Vehicle Safety Standards  flammability requirements without any added chemical retardants.

Chicco OneFit harness and headrest adjuster

The OneFit includes a no rethread harness. This allows you to just pull up on the orange tab on the top of the head rest to raise and lower the head rest and harness together. Adjusting the harness height is quick and easy.

Chicco OneFit inserts

The infant insert can be used from 5-11 pounds.

The head pillow must be used when using the infant insert. It is optional when rear or forward facing. The head pillow can NOT be used in booster mode.

Pro tip: when storing the unused inserts, write the car seat name on a piece of fabric tape and attach it to the insert so it’s easy to determine which seat it belongs to later.

Chicco OneFit harness covers

Both the harness pads and the crotch buckle cover are optional at any time rear or forward facing. Smaller infants may get a better fit without the harness pads in place.

Chicco OneFit rear facing lockoff

The OneFit has lockoffs on both sides of the seat for both rear and forward facing when installing with the vehicle seat belt. Like other Chicco lockoffs, we found these quite easy to use.

Chicco OneFit SuperCinch LATCH

The lower anchors on the OneFit feature Chicco’s SuperCinch LATCH system. With this system, the lower anchor straps are labeled “Pull 1st” and “Pull 2nd”. In many ways, SuperCinch can make the lower anchor install fairly simple.

Pro tip: pull the “Pull 1st” side as tight as it can go before pulling the “Pull 2nd” side.

Chicco OneFit lower anchor storage compartment

The lower anchor storage compartments are located at the side of each seat, near the booster belt path. They are easy to open and the lower anchor connectors store neatly inside.

Chicco OneFit recline options

Any of the 9 recline positions can be used rear or forward facing or in booster mode to install the seat at the proper recline angle based on the mode of use. Installing on level ground is preferred to be able to take advantage of the recline options. If you can not install on level ground, ensure the level line is parallel to the ground.

Chicco OneFit crotch buckle in the inner position

The crotch buckle strap should be in the position that puts it closest to, but not under, the child. The crotch buckle MUST be in the outer position when forward facing. It can be in either position when rear facing, based on fit to the child. To adjust the crotch buckle, remove the cover from the bottom of the seat. Then open the door in the bottom of the seat pan and move the buckle strap forward or back and close the door until you hear a click.

Chicco OneFit Cupfolder, folded in

The OneFit includes two of Chicco’s unique cup holders, they call them cupfolders. These cupholders can be folded in to save space (hence: cupfolders, so clever!). They are required to be installed while the car seat is in use, but can be removed for cleaning. They can be placed in the dishwasher on the top rack ONLY.

OneFit chest clip

The two position chest clip can be used in either the inner or outer position based on the fit to the child. There are no rules regarding which setting to use. We’d seen this chest clip on earlier versions of the NextFit and frankly, we’re not sure if we’re fans of it making a comeback because it can be a little confusing to figure out which setting is best for the child. It does, however, help with a very nice fit on the tiniest of passengers.

Chicco OneFit rear facing with seat belt in lockoff

To install the OneFit rear facing with the vehicle seat belt, place the child restraint on the vehicle seat with the harness facing the back of the vehicle. Choose a recline position that puts the bubble on the recline indicator within the rear facing range.

OneFit rear facing installed with the seat belt

Thread the vehicle seat belt through the blue rear facing belt path and buckle the seat belt. Push down in the car seat where the child’s bum goes and pull on the shoulder belt to remove the slack from the lap belt. While holding the shoulder portion of the vehicle seat belt tight, slide it into the lockoff on the side of the car seat opposite the vehicle seat belt buckle.

Chicco OneFit rear facing with lower anchors

To install the OneFit rear facing with the lower anchors, set the child restraint on the vehicle seat with the harness facing the back of the vehicle. Select a recline option that places the bubble on the recline indicator within the rear facing range. Open the lower anchor storage compartments on either side of the seat and remove the lower anchor connectors. Route the lower anchors through the blue forward facing belt path.

OneFit rear facing installed with lower anchors

Attach the lower anchor connectors to the lower anchors in the vehicle seat bight. Pull the side of the lower anchor strap labeled “Pull 1st.” Once you can no longer tighten that one, pull the side labeled “Pull 2nd” until the lower anchor webbing is secure.

Checking movement at the belt path

Once the seat is installed, give it a firm handshake at the belt path, make sure the seat moves less than an inch at the belt path.

Chicco OneFit newborn fit with the lower insert

This Huggable Images newborn doll weighs 7 pounds and is 17 inches long. We found that the newborn doll got a much better fit without the harness covers and the head insert. The head insert caused head slump, so we removed it. Our doll got a good fit both with and without the newborn insert.

With the insert, the harness sits well below the shoulder. The crotch buckle is in the inner position.

Chicco OneFit newborn fit without the bum insert

Without the insert, the harness sits right at the baby’s shoulder. The crotch buckle is in the inner position.

Chicco OneFit 9 months old

Our 9 month old model weighs 19 pounds and is 27 inches tall. He fits very well in the OneFit. The harness sits just below the shoulder and the crotch buckle is in the inner position.

Chicco OneFit 3 year old rear facing

This model is 3 years old, weighs 26 pounds, and is 37 inches tall. She has plenty of room to use this seat rear facing. The harness sits just below the shoulder and the crotch buckle is in the outer position.

Chicco OneFit forward facing with vehicle seat belt using lockoff

To install the OneFit forward facing with the vehicle seat belt, remove the top tether from the storage location at the back of the child restraint and loosen the adjuster webbing. Set the OneFit on the vehicle seat with the harness facing the front of the vehicle. Loosely connect the top tether to the tether anchor location in the vehicle.

Chicco OneFit forward facing installed with vehicle seat belt and top tether

Then, choose a recline position that places the recline bubble indicator in the forward facing range. Route the seat belt through the red forward facing belt path and buckle the seat belt. The back padding can be lifted for easier access to the belt path. While pushing down where the child’s bottom goes, pull on the shoulder belt to remove the slack from the lap belt. While holding the shoulder portion of the vehicle seat belt, slide it into the lockoff on the side of the seat opposite the vehicle seat belt buckle. Remove the slack from the top tether webbing.

Chicco OneFit forward facing installed with lower anchors and top tether

Remove the top tether from its storage location on the back of the OneFIt and loosen the adjuster webbing. Set the child restraint on the vehicle seat with the harness facing the front of the vehicle. Loosely attach the top tether to the tether anchor location in the vehicle. If the lower anchor connectors are in the storage compartments, remove them and route them through the red forward facing belt path. If they are in the rear facing belt path, open both storage compartments on the side of the seat and slide the lower anchor webbing into the red forward facing belt path. Then close the storage compartments. Hook the lower anchor connectors to the lower anchors in the vehicle seat bight. Then pull the lower anchor adjuster strap labeled “Pull 1st”. Once all the slack is removed from the first strap, pull the adjuster strap labeled “Pull 2nd” until the seat is installed tightly.Last step: remove the slack from the top tether webbing.

Pro tip: pull the “Pull 1st” side as tight as it can go before pulling the “Pull 2nd” side.

Checking movement at the belt path

Once the seat is installed, give it a firm handshake at the belt path, make sure the seat moves less than an inch at the belt path.

Chicco OneFit 3 year old forward facing

Our 3 year old model typically rides rear facing, but she likes to model so here she is again! She still weighs 26 pounds and is 37 inches tall. She has tons of room left to grow in this seat. The harness sits just above the shoulder and the crotch buckle is in the outer position. She was able to climb into the seat all on her own.

Chicco OneFit 5 year old forward facing

This model is 5 years old, 52 pounds, and 45 inches tall. He is nearing the harness weight limit on this seat but he is very comfortable. He was able to climb in and buckle himself easily. The harness sits just above the shoulder and the crotch buckle is in the outer position.

Chicco OneFit harness stored for booster mode

To convert the OneFit to booster mode, completely loosen the harness by pushing the harness release button and pulling the harness straps out as far as possible. Lift the backrest padding and undo both snaps on the lower backrest padding and pull that portion down. Remove the shoulder pads and crotch strap pad and store in a safe place for future use.

Chicco OneFit chest clip and buckle tongues stored

Connect both sides of the chest clip together, then slide it down until it meets the buckle tongues. Then, insert the chest clip and buckle tongues into the storage compartment at the bottom of the seat back.

Chicco OneFit crotch buckle stored

Next, remove the crotch buckle from the seat and place it in the storage compartment under the bottom padding. Reattach the backrest padding and the OneFit is ready for new life as a booster seat.

Chicco OneFit 5 years old booster mode

Our 5 year old model is back. He still weighs 52 pounds and is 45 inches tall. He usually rides in a harnessed seat since he isn’t quite mature enough for a booster full time. Unfortunately, since the seat is rather wide, he wasn’t able to buckle the seat belt himself. The belt fits him very well. It sits nice and low on the hips, touching the thigh. The shoulder belt is centered on the collar bone.

Chicco OneFit 8 year old booster mode

This guy is 8 years old, weighs 66 pounds and is 51 inches tall. He was not able to buckle himself in either because the seat sits up just a little too high for him to be reach the buckle. However, the seat belt fit continues to impress. The lap belt sits low on the hips, touching the thighs and the shoulder belt is centered on the collar bone. He was very excited to let me know how soft the seat was!

Chicco OneFit 11 year old booster mode

Our 11 year old model weighs 72 pounds and is 54 inches tall. The seat belt touches the thigh and sits low on the hips. The shoulder belt sits on the collar bone. This model has a half inch to one inch of torso growth before he outgrows this seat in booster mode. He was able to buckle himself, we suspect that’s because he has more booster experience than our younger models.

Chicco OneFit manual storage

Date of Expiration

The OneFit expires 10 years after the date of manufacture. This can be found on the date of manufacture label on the bottom of the seat base and on page 12 of the manual.

Chicco OneFit date of manufacture, expiration date, and FAA approval

Date of Manufacture

FAA Approval

Top Tether Storage

OneFit Top tether anchor storage on back of seat shell

The top tether stores in a compartment on the back of the seat shell, under a door.

Overall Thoughts

Like other Chicco multimode car seats, the OneFit impressed us in many ways. It fits a wide range of children from newborn to upper elementary age — not many seats can say that (and have it be true!). It’s a rare occasion that a multimode car seat can truly fit kids for ten years since the booster mode seat belt guide is often too low to provide a proper booster fit for older children, but the OneFit offers all of that! The ease of use features such as the lockoffs, SuperCinch LATCH, and no rethread harness make installing and using the child restraint a breeze.