Nine months may seem like a long time when you’re excited for your little one to arrive. But when you look at your list of baby-related to-dos, it definitely doesn’t seem like much time. You’ve got to do the nursery, find a pediatrician, make appointments, develop a birth plan, get supplies, and maybe even take a childbirth class. And this is just to name a few! One of the most important tasks for your newborn’s safety is installing the car seat. 

If you’re looking at your calendar, you’re probably wondering when’s the best time to install your car seat. This is a tough one for many! Some think the earlier, the better. Others think it’s no big deal to wait until a few days before that due date. To help you answer this question, this post tells you when to install your car seat based on safety. Here’s when you need to get that seat in your car:

When To Install Car Seat

The best time to install your infant car seat is in your final trimester—better yet, wait for the final few weeks. We don’t recommend putting it in too early simply because if you get in an accident, that car seat would need to be replaced. You probably don’t want to replace a car seat you’ve never used. So, by reducing the amount of time that the car seat sits in the vehicle, you lower the risk of it getting damaged. 

Additionally, your newborn will ride in a rear-facing car seat to start out, which may require you to slide one of the front seats forward. If you’re pregnant, you may not have the extra space yet for baby’s car seat and your belly. If it seems like the seat will prevent you from sitting safely yourself, definitely consider installing it later on in pregnancy. 

More importantly, though, it’s essential you don’t install the car seat before you’re properly educated on car seat safety. We recommend The Infant Course to become totally familiar with the child restraint system and the installation process. You can’t know what you don’t know, so a car seat safety course will fill in all the gaps! It’s one of the best ways to keep your newborn baby safe. (Or, any age kid since your child will likely be in a restraint system until about 12 years old.)

Car Seat Installation Tips 

Read your manuals. 

The vehicle owner’s manual and the car seat manufacturer’s manual both hold valuable information you need for the car seat installation process. Read the car seat section of your vehicle manual all the way through and read your car seat manual cover-to-cover. This will help you determine the best place to install the car seat, how to install the car seat, and how to use it once it’s in. (You should do this for every new seat you get from the infant carrier to the booster seat.)

Double-check the height and weight limits. 

Next, you need to double-check the lowest and highest weight or height requirements. Obviously, your newborn baby won’t be too big for their seat. But you do need to know the installation processes for your new baby’s small size. The seat will have to be rear-facing and likely include the newborn padding, the lowest recline level, and the lowest adjustments on the harness straps. 

If your child is premature and hasn’t reached the weight minimum, look at other car seat options on our preemie car seat post

Install on level ground. 

The car seat has to be set to a specific recline needed for the newborn stage. Most car seats have bubble indicators that help you determine if you have the right adjustment. However, if you’re not on level ground, the bubble may be deceiving. Find a flat surface to do your installation. 

How to Install an Infant Car Seat

Decide between LATCH or belt installation. 

For newborns, there are two options for installation on your car seat. The LATCH system (Lower Anchors and Tether for Children) uses your vehicle’s built-in anchoring system to install a car seat. The other uses the vehicle seat belt. We always recommend the seat belt installation because the LATCH system is only suitable for 65 lbs (including the car seat). This means you’ll have to install it using the seatbelt at some point, so we think it’s smart to do it from the start. 

Note: Do not ever use LATCH and seat belt installation unless your car seat manual specifies that’s correct.

Install & Use Car Seat for Infant

Get in the car seat when you tighten it. 

Getting a car seat installed tightly with the seat belt can be difficult. We find sometimes the best way to get that secure fit is to first get yourself into the car seat (or preferably someone else helping you who’s not pregnant.) Plant your knee or bottom into the car seat, and then pull those straps tight. It’s a great hack that makes installation much easier.

Ensure your seat doesn’t move. 

Once you have the seat properly installed, use your non-dominant hand at the base of the car seat and try to move it. If the seat moves more than one inch in any direction, it needs to be tighter. (Yes, get back in the car seat.)

How Tight Should Car Seat Be?

Check for twisted straps. 

Before you’re finished, check the shoulder belt, lap belt, and harness straps for any twists. Twists compromise the integrity of the belts, so it’s really important they’re all flat. Double-check them before marking this off your to-do list.


Even though car seats seem straightforward, there’s usually a learning curve to everyday use. They’re more challenging than you may think! Practice fastening your baby in the car seat with a doll and get used to taking the carrier out, carrying it around, and putting it back in. Doing this will give you peace of mind that when your child is ready to ride, you’re ready to get them where they need to go safely. 

Get it approved by a professional. 

To confirm you didn’t make any common car seat mistakes, you need a child passenger safety technician to do a car seat inspection. (No, do not take your car seat to a fire station.) You can find a tech in your area HERE or you can do a digital consult with us in the comfort of your own home! We’ll do a full car seat check, answer your questions, and even help you install it right there during the consultation. This step is essential for your peace of mind and the safety of your new baby. 

Make sure you’re safe, too!

Follow these tips:

  1. Adjust the steering wheel to the highest position and tilt upright if possible.
  2. Move the headrest so the thickest part is directly behind the head.
  3. Adjust the vehicle seat back to an upright position.
  4. Sit as far back from the steering wheel as possible. The belly should not come in contact with the wheel.
  5. Position shoulder belt between neck and end of shoulder, lying snug and flat between breasts.
  6. Lap belt snug and tight UNDER the belly, laying flat across top of thighs.

Install your car seat in the final trimester.

The best time to install your car seat is a few weeks before your due date and after you’ve taken a car seat safety course. If you haven’t purchased your seat yet, also consider our car seat buying kits that’ll help you find the perfect car seat for your needs and lifestyle. And stay up-to-date on our blog posts, YouTube videos, and Instagram uploads for all the must-have car seat safety advice. We can work together to keep your newborn safe for every ride, from baby’s first trip home to their car seat graduation.

Find your best car seat in *under 5 minutes*

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