Britax Allegiance 3 Stage Convertible Car Seat Review

A car seat is designed for easy and safe transportation of your baby in any vehicle. The need for a car seat becomes more essential if you have a small baby or a toddler. In addition to a car seat, it is not just a seat for your infant but is specially designed for safety purposes. It protects your baby from shocks and impacts in any kind of collisions. 

The type of car seat depends upon the weight, height, age, and other factors of your child. 

There are various types of a car seat:

  • Infant car seat
  • Convertible car seat
  • 3-in-1 car seat
  • Booster seat

Among these types, we are going to discuss convertible car seats. These car seats can be converted into 2 different modes. The convertible car seats can be a good partner for your child from being an infant to a toddler. 

These car seats are manufactured and designed for growing babies i.e. from an infant to toddlers. Thus it is better to buy a convertible car seat so that it can be used for your child until he gets rid of this seat. 

A convertible car seat offers forward-facing mode and rear-facing mode. Various parents choose the convertible car seat because they come with more height and weight ranges as compared to other car seats. They are highly padded so that the baby can have extreme comfort. Such padding not only provides protection but also it absorbs impacts while in an event of collision.

Finding the most suitable car seat for your baby among an immense variety is a hard task but there is no need to worry as we are always here to help you. 

Here in this content, we are discussing a convertible car seat offered by Britax. Below you will see a detailed description of the Britax Allegiance 3 Stage Convertible Car Seat.

Britax Allegiance 3 Stage Convertible Car Seat Overview: 

For your growing child, the allegiance by Britax is a safe and comfortable car seat while you are on the go. The installation of this car seat is a breeze with the built-in lock-offs and push-button latch connectors. The Britax is designed with safety technologies; this car seat features a patented Safe Cell impact protection system. This protection system includes a premium quality steel frame, an impact-absorbing base, side impact protection, and a V-shaped tether that reduces the forward movement. There is a strong layer of side energy absorption in the allegiance convertible car seat. A foam-lined shell shields your baby from side-impacts in the event of any collision.

In addition to these safety features, foam padding and 3-recline positions will keep your child safe, comfortable and cozy along the journey. The harness and headrest allow you to never have to rethread again and they can be adjusted in 10 different positions. The allegiance car seat can be used as rear-facing with a weight capacity between 5-40 pounds and as forward-facing with a weight capacity between 20-65 pounds. The maximum child standing height of this seat is 49 inches or less. The dimensions of this car seat are 18.5 x 26 x 21 inches.  The harness slot height ranges from 8.5 inches to 17.5 inches. The body pillow is removable and the seat cover machine washable. The seat is FAA-approved. 


Britax Allegiance 3 Stage Convertible Car Seat 1 Layer Impact Protection – Rear & Forward Facing – 5 to 65 Pounds, Static


Following is the detailed description of the Britax Allegiance 3 Stage Convertible Car Seat:

Weight capacity:

The allegiance car seat has two modes of seating i.e. the rear-facing which has a weight capacity between 5-40 pounds and the forward-facing mode with a weight capacity between 20-65 pounds.

Height range:

The child standing height range of this convertible car seat is 4.9 inches or less than this. The child seated shoulder height for rear-facing mode is 9-16.75 inches and that for forward-facing mode is 12-16.75 inches.  

10-position harness: 

This convertible car seat offers 10 different harness height slots. These heights are 8.5” / 9.5” / 10.5” / 11.5” / 12.5” / 13.5” / 14.5” / 15.5” / 16.5” / 17.5”. This 10-position harness is perfect for your growing baby. 

Side impact protection:

The car seat is made from a foam-lined shell which protects your baby from impacts thus your baby is safely secured. 

SafeCell impact protection: 

This car seat features a patented SafeCell impact protection system. This protection system includes an impact-absorbing base, side-impact protection, a premium quality steel frame, and a V-shaped tether that reduces the forward movement.

Lower anchors:  

The seat is locked into a place with just a click and is released with the push of a button. 

Built-in lock-offs: 

The installation of this seat has become a breeze with the help of the built-in lock-offs.

Easy to remove cover: 

The cover of the seat is easily removable. Thus when it gets dirty you can remove it and wash it in the machine as the fabric is machine washable. You don’t need to remove the harness for removing the seat cover.

3-position recline: 

The 3-position recline offers adjustment for your baby’s comfort and provides the safest installation angle. 

Easy-buckle system: 

The buckles and straps of the seat keep out of your way while putting baby in and out of the car.

Removable body pillow: 

The body pillow is removable and ensures snug fit of even small newborns in the seat. When you don’t need the infant insert you can easily remove it. 


Brand: Britax
Color: Static 
Seat type: Convertible car seat
Installation type: LATCH
Material: Steel
Orientation: Forward-facing, rear-facing
Dimension: 19 x 18.25 x 29.5 inches
Weight: 19.5 pounds
Maximum weight recommendation: 65 pounds
Minimum weight recommendation: 5 pounds 
Maximum height recommendation: 49 inches
Model number: E1C147Z
Style:  1 layer impact protection
Rear-facing minimum child weight: 5 pounds
Rear-facing maximum child weight: 40 pounds
Forward-facing minimum child weight: 20 pounds
Forward-facing maximum child weight: 65 pounds


  • Rear-facing mode (5-40 lbs.)
  • Forward-facing mode (20-65 lbs.)
  • Patented V-shaped tether
  • Safe Cell impact protection
  • Built-in lock-offs for easy installation
  • 5-point safety harness
  • Side impact protection
  • Premium Quick-push LATCH connectors


  • Nap-friendly padding and fabric
  • 3-position recline
  • High strength steel frame 
  • Flip-forward buckle
  • Removable body pillow
  • Easy to remove color
  • 10-position harness
  • Easy buckle system 


  • The harness of the seat can be adjusted in 10 different positions according to the requirement.
  • The seat cover is removable and is washable.
  • The seat cover can be removed without removing the harness.
  • The infant insert of this seat is also removable so when it is not required you can easily remove it.
  • The Britax offers both forward and rear-facing seating positions.
  • This seat is useful and will support your child through the journey from an infant to an adult one.
  • This car seat offers a maximum child standing height of 49 inches or less.
  • It is approved by FAA.
  • The three recline positions of the seat keep you baby comfortable and cozy in the whole ride. 


  • This seat is FAA-approved but it cannot be attached to the airplane seat.


The Britax allegiance 3 stage convertible car seat is more than enough. It will prove to be a good companion of your growing child. It offers the best safety features. Give a chance to this convertible car seat and purchase it for your child.