Let's Talk About Car Seats: How to Install your Seat Correctly

I probably should’ve started with this post since proper harnessing is pretty much irrelevant if your seat isn’t installed correctly, but we’ll just live and learn here. This is long, but it’s not tough to read. I don’t think.

Installation can be one of the more daunting challenges to parents, especially new parents, because there is a lot to manage. The terms are unfamiliar, the rules are changing and all you really want is to keep your child safe. Every parent and caregiver should know how to install the car seats that are or could be in their car. You never know when someone will accidentally unbuckle the seatbelt holding your seat in place or when you’ll need to move it around. Having only one designated installer is a recipe for disaster.

So, how do you install a car seat? I’m going to break it down into two categories- rear facing and forward facing seats. Boosters are a class of their own (most of the time you just set it in the seat and buckle your child in), so we aren’t going to touch on those today.

For either rear or forward facing, the same first 3 steps apply:
1. Read the manual. Seriously, before you touch the seat or set it anywhere near the car, read the manual.

2. Figure out what installation method you’re going to use. There are 2 basic methods- a seatbelt installation and a LATCH (lower anchors and tethers for children) installation. The seatbelt installation requires that your seatbelt is “locked” in some fashion, the LATCH installation requires that your car has lower anchors (all vehicles since 2002 have lower anchors). LATCH and seatbelt are EQUALLY SAFE when used properly and neither are tough to do once you’ve practiced a few times. There is also a new law that states that LATCH can only be used until a combined weight of 65 pounds, so find out your child’s weight and your car seat’s weight (should be available online if not in your manual) and see if LATCH is an option.

3. Pick your seat location. Statistically speaking, the middle seat is the safest position in the car. The chance of injury is 40% less in the middle, as it is farthest from any impact point. If you are choosing to do a LATCH installation, you must check your car manual to find out if you have anchors in the middle seat. Few cars have dedicated middle anchors and most cars and car seats forbid you from borrowing, or using one outside anchor from either side, to install the seat in the middle. Many car seats also forbid this, or require a very specific distance between anchors.

1. Find the angle indicator on your seat. Most infant seats have a level bubble or color zone that indicates the right angle for the seat. Many convertibles have lines that should be level to the ground. If using a convertible, your seat may need to be reclined to a certain level (specified in your manual). If using an infant seat base, you may need to rotate a dial to make the recline foot higher or lower to get the right angle. If your seat isn’t adjustable and isn’t within the proper angle range, check your manual, but most car seats allow a tightly rolled towel or a pool noodle (or a pyramid of 3 noodles) to be put under the seat at the bite (where the back and butt portion of the vehicle seat meet) to help recline it further.

This is the angle indicator on Eli’s seat in my husband’s car. It offers two zones- one for infants younger than age 1, one for older kids. Ground level should fall somewhere within those two zones (we actually have it pretty well reclined- this seat sits very upright and cause Eli’s head to fall forward when he sleeps)
angle indicator

2. Install the seat using the method chosen in step 2.

2a. Install using a locking seatbelt. Figure out how your seatbelt locks- there are a few options (all of which will be described in your car’s manual), most reasonably recently produced cars have a switchable retractor, meaning they’re not locked during normal use, but if you pull the seatbelt all the way out gently, you can feed the belt back and it will be locked. For this type of belt, thread the belt through the appropriate belt path (it will be labeled and specified in your manual, this is important) and buckle it. Then pull the belt all the way out, and feed the slack in. Put pressure on the seat and pull the belt as tight as you can, feeding the belt back into the retractor as you go. Sometimes seatbelt installations result in a slight tilt on the side opposite the buckle so you may need to put more pressure on that side of the seat to keep it straight (though a slight tilt is not a safety issue as long as the install is tight).

This is our carseat installed with the seatbelt. Our cars do not have center LATCH, so to keep Eli in the middle, we use the seatbelt. If we’re being honest, I prefer seatbelt installs almost 100% of the time.

2b. Install using seatbelt lockoffs built into the car seat. Some car seats have seatbelt lock offs built in. These work to lock the seatbelt without locking at the retractor. They’re no safer, but are sometimes easier. To install with this, thread your seatbelt through the belt path and into the lock off as described by your manual. Put pressure into the seat, tighten the seatbelt as much as possible, then close the lock off.

This is an example of a lock off (the blue thing). The seatbelt gets threaded through, then without actually locking the belt, you pull all the slack off and close it. The seatbelt is held tight and for the most part they’re pretty easy. I have lost many a finger nail on these, however.

2c. Install using LATCH. Hook your LATCH connectors onto the anchors. Put pressure into the seat, then tighten the strap until the seat is secure.

These are LATCH connectors. Some will be more like top tether hooks (pictured below), but these are the newer, easier to use style.

3. Check your installation. Double check that your angle is still within the normal range. Then check for movement. Using your non-dominant hand at the belt path, move the seat side to side and front to back using about the pressure you’d use for a firm handshake. It should move less than an inch in all directions.

4. Hook your top tether- IF APPLICABLE There are only a small handful of car seats that allow top tethering in rear facing mode (Britax, Combi, Peg Perego, Diono, that I know of) and you must check your manual. If it doesn’t specify that you can do this, then you cannot and should not do so. If your seat allows it, it will come with a D-ring that you will loop around a stationary part of your car, likely the seat track. Clip the top tether to the hole on the d-ring, then tighten just until the slack is out. Store any extra harnessing from the tether.

Here is the top tether, it’s currently not in use, but this is what they typically look like.
top tether


HOW TO INSTALL A FORWARD FACING CAR SEAT I highly, highly recommend you check the strap height on your seat before installing it. If your seat has a manual rethread harness (that is, you can’t pull a lever and raise the straps) it’s virtually impossible to do this once it’s been installed forward facing.
1. Make sure your seat is set for forward facing. Some convertible seats have a rear facing boot/recline setting, so make sure you’ve stored that or set the seat to the appropriate setting. Your manual will specify.

2. Install the seat using the method chosen in step 2 from above. The steps for this are exactly the same as above in 2a, 2b, 2c.

3. Check your installation. Using your non-dominant hand at the belt path, move the seat side to side and front to back using about the pressure you’d use for a firm handshake. It should move less than an inch in all directions.

4. Attach the top tether All convertibles and combination seats should have a top tether for forward facing. This tether was created to help reduce head excursion in the event of an accident by holding the top of the car seat secure to the vehicle seat. You’ll need to check your manual for top tether locations, but as long as you have a top tether anchor, you should absolutely use it when installing forward facing. Hook the top tether to the anchor, then tighten just until the slack is out.


Later this week I’ll go over some common installation errors that I grazed over quickly here. Please know that I never judge parents for things like this. I have installed just about every one of Eli’s seats incorrectly at some point. It’s a learning experience, it’s just one where we want to eliminate as many errors as quickly as possible.

Please feel free to ask questions in the comments.