Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views :

Safety 1st OnBoard 35 LT Car Seat Review

The Safety 1st OnBoard 35 LT car seat is $144 on Amazon

The Safety 1st onBoard has been around for many years, going through various permutations of seat and base combinations along the way.  It’s been a consistent seat with a lot of ease of use and comfort features at a reasonable price point.  We were eager to see the latest version — the onBoard 35 LT.

See below for our full Safety 1st OnBoard 35 LT car seat review
Last updated August, 2018

Quick Stats

  • Weight range: 4-35 pounds
  • Height range: 19-32 inches tall
  • Shell height: 20 inches
  • Lowest harness position: 5 inches without the insert, 4.5 inches with the insert
  • Weight (carrier only): 7.9 pounds
  • Expiration: December after the seat’s eighth birthday
  • Handle position: Must be up while being carried or in the car


  • The newest onBoard 35 advertises itself as the “lightest infant car seat” that last until the child 32 inches tall or weighs 35 pounds.  It’s not wrong.  At a svelte 7.9 pounds, this may be the lightest rear facing only carrier on the market.
  • 8 year plus lifespan means plenty of time for a growing family to use the seat.
  • Clearly written, easy to follow manual includes obvious illustrations to instruct and make adjustments less confusing.


Installation With the Base

Lower Anchors

The base has hook on lower anchors that are easily routed through the belt path and attach without issue to the car.  The belt path is open enough to pull the tail of the lower anchor webbing and tighten the strap without an issue.

There’s enough flat space to add weight comfortably to the base while tightening, making installation with lower anchors fairly simple.

Vehicle Seat Belt

Installing the onBoard 35 with the seat belt is just as easy as installing with the lower anchors.  The space for the vehicle seat belt is wide, with a lip at the top so the seat belt stays in the right area during installion.  The vehicle belt guide is marked above the lip.Because the base is lightweight, using the seat belt may cause the base to tip.  If this is the case, contact Dorel (the parent company of Safety 1st) for a free locking clip.

Recline Angle

The base has a recline that is easy to find and use, but has it only two positions.

I found in my back seat the more reclined position was perfect, but because there are only two positions, it may be necessary to use a rolled towel or pool noodle to get the appropriate angle.

The recline for the seat is on the carrier portion, and is a single recline line.  There are no indicators on the base, nor a range allowed.  The line must be parallel to the ground below the vehicle at all times.

Installation Without the Base

Without the base, the seat is very compact and easy to install.  The belt guide is well marked and the instructions in the manual are quite clear. The seat installed at a nearly correct angle with very little effort.I was able to change the angle easily, and install the seat was properly in a very short time.  To install the onBoard 35 without the base, thread the lap portion of the vehicle seat belt through the open belt guides on the carrier portion of the seat. Lock the vehicle seat belt, add weight to the seat while pulling the seat belt is pulled tight.


The onBoard 35 has large harness slot openings, making it quite easy to adjust the harness height.  There are two different loops on the shoulder straps, making the seat a great fit for small and large babies.There are three crotch strap positions, with a fourth option for newborns who are much smaller.  The crotch strap can be shortened while on the innermost position for preemies, though I found that my preemie doll nearly didn’t need it.

The slot heights: 5, 7, 9, and 11 inches (without the insert, subtract a half inch when the insert is in) will accommodate a wide variety of children.  Even the 31 inch tall 16 month old doll didn’t need the top harness slots — that model used the second to top harness slot and still had several inches of growing room above his head.

The seat’s stated height limit of 32 inches tall or 1 inch of shell above the child’s head is tall enough to accommodate most children to that height.  Because the carrier portion of the seat weighs only 7.9 pounds, it’s actually far more viable to believe a parent can carry a heavier or older child in this seat for longer, making it a great option for parents who prefer to use a carrier style car seat for an extended period.

Fit to child: Preemie

At 4 pounds and 17 inches long, our  “preemie” doll represents the average small preemie.

I’m very happy with the fit to the preemie doll with this seat. 

More and more seats are having better fits for the smaller riders, and it’s nice to see manufacturers taking them into account.

Traditionally, the onBoard has been fantastic with the four pound babies, and this one is no exception.


Fit to child: Newborn

The seat ships with the harness straps in the second to lowest harness height, which was fine for the newborn doll. To fit the preemie doll, I moved the harness straps down, made sure the inner loops on the back of the harness were being used, and adjusted the crotch strap to the shorter optional length.

Had this model been a real human, the crotch strap adjustment wouldn’t have been required. We find that our preemie doll often requires a shortened crotch strap in instances where a human child wouldn’t. The shortened crotch strap made the fit astonishingly good — the harness straps are low on the doll’s hips and there’s enough room to move the chest clip to the right place. I did have a hard time buckling the shortened crotch strap, which could be an issue with a tiny human rather than a pliable doll.

The seat fit the newborn doll well.  I needed to make zero adjustments.  The harness straps were below the shoulders, the crotch strap a decent length, and the harness tightened perfectly.  The inserts are optional at all ages — this newborn doll fit properly both with and without the inserts.

Fit to child: toddler

Previous versions of the onBoard seats fit small babies well, then accommodate them right up until they’re big babies, but this seat seems to even outstrip its own limits. Which is amazing.

I was surprised to move the straps DOWN from the top for the 16 month old doll.  There was a comfortable amount of room in the crotch area with the strap on the outermost position as well.  The harness was easy to loosen and tighten for this size child, and buckling was a snap.

Features of the OnBoard 35 

Extra Padding

This seat has nice internal padding, though I found that the headrest fell out easily.  It must be used with the body pillow, you cannot use just the head rest alone. However, you can use the body pillow without the headrest.  They’re both optional at all times.


The main feature of this seat is the carrier’s light weight. It’s just under eight pounds, making it the lightest rear facing only car seat I’ve worked with.  And I’ve worked with quite a few.

I weighed the seat to see if it really was the lightest rear facing only carrier that goes to 35 pounds.

And it is.  It was so light that after I weighed it, I put it on a basket of dirty laundry and carried them downstairs. I didn’t even notice the weight of the carrier.

Easy to Read Manual

The manual covers more information than I thought possible, and I was very excited to read it and see the ease with which it conveyed that information. The sections are color coded and intuitive. I can’t think of anything more that needed to be added to the manual. This is high praise indeed!

Where to Find

FAA Approval: The FAA approval label is on the main sticker at the child’s left shoulder.  Like other Dorel car seats, the onBoard 35 has a picture of an airplane in addition to the standard red sentence, making it easier for parents and flight attendants to find quickly.

Manual Storage: The manual stores on the underside of the carrier, right near the crotch strap, under the harness adjuster strap.  It’s easy to get in and out of its storage area.

Expiration: The seat is stamped on the back to discontinue use after the December after the seat’s eighth birthday.  For instance, this seat was made on November 4, 2016, and it can be used until December 31, 2024.  The 2024 is stamped on the back of the seat.

Final Thoughts

The onBoard 35 will fit a variety of babies large and small well for an extended period and is lightweight. It’s compact when installed in the car, decently narrow, and easy to install.  There are a few things I wasn’t as fond of: the base lacks a wide range of recline options, the seat requires a single recline line be parallel to the ground at all times, and the single recline line’s location on the seat itself instead of on the base.

However, at this price point, you’re getting a lot of seat that is not generally difficult to install or use.  The onBoard 35 LX is a well-priced option that fits a wide variety of babies from small to large.


safety 1st onboard 35 LT

Where to Buy

The Safety 1st OnBoard 35 LT car seat is $144 on Amazon

As always, all opinions included in this review are our own. 

Working Parents Handbook did not receive and does not accept any solicitation or compensation for this review from Safety 1st or its affiliates. 

Working Parents Handbook may earn commissions from links included on this page.