What is the Difference Between an Infant, Convertible, All-in-One and Booster Car Seat?

Does the thought of buying a car seat send you into a tail-spin? Are you overwhelmed with options and aren’t sure where to turn? Are you having issues figuring out which car seat is the best fit for your child? Well, take a deep breath and read below!

There are 5 major categories of car seats:

  1. Infant Car Seats
  2. Convertible Car Seats
  3. Combination Harness to Booster Car Seats
  4. Belt-Positioning Booster Seat
  5. All-in-One Car Seats

Let’s go through them individually and use this guide to help you find the right fit for your child.


Infant Car Seats

  • Base of infant seat is removable and stays attached to your vehicle car seat (additional bases are sold separately).
  • Designed to be used on average from 4lbs to 30 or 35lbs and up to 32” (weight and height limitations vary by make and model of car seat).
  • Rear-facing ONLY 
  • Bucket style design to properly support developing infants.
  • Click and Go technology allows you to snap in your infant seat easily into your its base in your vehicle and remove it when needed during errands.
  • Many infant seats will also easily click into a stroller (of the same brand) with no other adapter necessary. [Additional adapters can be purchased separately if you use a different brand of stroller than your infant seat – Compatibility needs to be verified].

Convertible Car Seats

  • Can be rear-facing OR forward-facing
  • Designed to be rear-facing from 5-40 lbs
  • Designed to be forward-facing from 1 year AND 20 lbs, up to 65 lbs and 49”
  • Car seat is one complete unit with no detachable base
  • Car seat is not designed to be removed during errands. Only baby comes out.
  • Convertible seats will last from birth through the toddler years due to their higher weight/height capacity.
  • Most seats will have several recline positions to accommodate infants and toddlers.
  • Some seats will feature a cup holder.

Combination Harness to Booster Car Seats

  • Designed to accommodate forward-facing children from 2 years AND 25 lbs, up to 90 lbs in the 5-point harness mode.
  • Designed to accommodate forward-facing children from 40 lbs up to 120 lbs and 62” in the belt-positioning booster mode. [Always refer to owner’s manual for exact height and weight limitations for your exact seat.]
  • Some will have a mild recline option.
  • Some will include child cup holders.
  • This will be the last seat you ever need!

Belt-Positioning Booster Seats

  • Designed to raise your child so that the vehicle’s lap and shoulder belt fit correctly on their hips and shoulder.
  • Suitable for children from 40-120 lbs and from 38-63” in height.
  • Should only be used with BOTH the lap and shoulder belt. Not designed for use with only a lap belt.

All-in-One Car Seats

  • These are designed to be the ONLY car seat you ever need.
  • Most will last 10 years and will be suitable for children between 4 – 120 lbs.
  • Most will rear-face from 4 or 5lbs – 50lbs and up to 49″.
  • Most will have a forward-facing harness weight of up to 65 lbs and up to 49″.
  • Most will function as a booster from 40 – 120 lbs and from 44″ – 63″. 
  • These seats do not have a removable base. 
  • These seats do not come out of vehicles during errands. Only baby comes out. 
  • They feature several recline positions to accommodated your growing child and different stages of car seat safety. 
  • They may feature a cup holder. [Child favorite!]

A few safety tips….

Although children can legally forward-face at 1 year AND 20 lbs, it is HIGHLY recommended that they remain rear-facing until at least 2 years of age or even better, until the reach the maximum rear-facing height/weight of their seat.  It is also recommended to keep your child in a booster until 63” or 120lbs. The NHTSA advises parents to keep children in their respective seats until they reach the maximum height and weight requirements. Belt position is incredibly important in keeping your child safe in the even of a crash, and car seats allow you to get the best fit for your child.

** When using car seats for multiple children, make sure to check the expiration date and discard of your seat when appropriate. Most seats will last 5-7 years before expiring. 

Want more?

Now that you know all about the types of seats on the market today, read our blog below and see what type of seat your child should be in based on height, weight and age.

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One thought on “Car Seat 101 – The Difference Between an Infant Bucket Seat, Convertible Car Seat, All-in-One, Harness to Booster and Belt-Positioning Booster Seat

  1. Wet Nurse says:

    Option two is to buy a car seat and a stroller that can be connected using an adapter piece. If you re interested in a stroller that isn t quite newborn compatible (with a bassinet or deep recline to support a new baby s neck and squishy body), infant car seat adapters are available for a number of stroller brands do a search for “car seat adapter” and your stroller. This option allows you to use your regular stroller from day one, then keep using it once baby outgrows the infant car seat.

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