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Britax

Britax One4Life Convertible Car Seat, 10 Years of Use from 5 to 120 Pounds, Converts from Rear-Facing Infant Car Seat to Forward-Facing Booster Seat, Machine-Washable Fabric, Iris Onyx

  • Based on 1,164 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Nov 24
Order within 13 hours and 43 minutes
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Style: One4Life


Color: Iris Onyx


Features

  • 10 YEARS OF USE: The Britax One4Life all-in-one car seat delivers comfort and security from 5 to 120 pounds and up to 63 inches tall
  • ONE CAR SEAT FOR LIFE: This car seat features 4 configurations, including rear facing infant car seat, rear facing toddler car seat, forward facing 5 point harness car seat, and forward facing high back booster seat
  • INSTALL WITH CONFIDENCE: ClickTight(R) technology makes installation easy simply open the seat, thread and buckle the seatbelt, and click the seat closed
  • SAFETY YOU CAN TRUST: Equipped with a steel frame, SafeCell(TM) crumple zone, patented V-shaped tether, and two layers of energy management
  • A SECURE FIT IN SECONDS: The 15-position headrest and harness move together using one hand, so you can quickly find the proper fit as your baby grows (no rethreading)
  • REMOVABLE INSERT AND PILLOW: Helps keep your baby safe and comfortable under 20 lbs, and the tag-free headrest and pillow provide additional comfort and support without irritation
  • 9-RECLINE POSITIONS: Quickly adjust between 9-recline positions and use the easy-read level indicators to find the correct angle for your vehicle
  • PREMIUM PADDING AND COMFORT: The built-in cooling channels and ventilated mesh improve air flow to keep your child comfortable during every trip
  • DISHWASHER-SAFE CUP HOLDERS: The 2 removable cup holders can be used for your little one's drink or snack and easily twist out for cleaning between rides
  • MACHINE-WASHABLE COVER: The easy-to-remove car seat cover is safe to machine wash and dry; fabric and foam construction is naturally flame retardant

Description

Enjoy safe travels from birth to big kid with the Britax One4Life all-in-one car seat. This car seat features 4 configurations, including rear facing infant car seat, rear facing toddler car seat, forward facing 5 point harness car seat, and forward facing high back booster seat. Start with the rear facing car seat for infants and toddlers, then graduate to the forward facing car seat and booster car seat for preschoolers and big kids. ClickTight technology makes it easy to install your new baby car seat with confidence. Simply open the seat, follow the path to thread the seat belt, buckle it, and click the seat closed. The One4Life all in one car seat is outfitted with a high-strength steel frame, a SafeCell crumple zone, and a patented V-shaped tether. The protective seat shell and foam-lined headrest help absorb impact energy and are designed to help keep your child's head, neck, and body safe. Adjust the 15-position headrest and no-rethread harness at the same time, so you can find a secure fit in seconds. Quickly adjust between 9 recline positions and use the easy-read level indicators to find the correct angle. The Britax One4Life comes with an easy-to-remove, machine-washable cover, and the knit construction is naturally flame-retardant.

Brand: Britax


Installation Type: Seat Belt


Material: Polypropylene


Color: Iris Onyx


Orientation: Forward Facing


Product Dimensions: ‎20.5 x 19.5 x 25 inches


Item model number: ‎E1C903Y


Minimum weight recommendation: ‎5 Pounds


Maximum weight recommendation: ‎120 Pounds


Maximum height recommendation: ‎63 Inches


Material Type: ‎Polypropylene


Material Composition: ‎steel


Care instructions: ‎Machine Wash


Style: ‎One4Life


Number of reclining positions: ‎15


Batteries required: ‎No


Orientation: ‎Forward Facing


Rear-facing minimum child weight: ‎5 Pounds


Rear-facing maximum child weight: ‎50 Pounds


Forward-facing minimum child weight: ‎22 Pounds


Forward-facing maximum child weight: ‎120 Pounds


Harness type: ‎5-Point


Item Weight: ‎30 pounds


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Nov 24

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Favorite seat! Read for fit tips
Style: One4Life Color: Glacier Graphite
Review Image by RaeMars23 RaeMars23
My car seat hater enjoys the car much more in this than his infant seat. My 3 year old has one too and we love how comfortable they are, the less strict accident policy (had to replace a Graco extend 2 fit twice in 6 months bc of their replace in any and all accidents policy), that you can machine wash the cover with light detergent and how easy they are to install. Very high quality car seat that's very easy to adjust! CARSEATS WILL NOT PROTECT YOUR CHILD IF USED INCORRECTLY: -Top of chest clip should be level with armpits -Straps should come from below the shoulders rear facing and above the shoulders for forward facing -Slack should be removed from the hips, then tighten just enough so you're unable to pinch the straps at the shoulder vertically -DO NOT add any inserts, strap covers or head positioners that didn't come with your seat, they are not crash tested for your seat and will void the warranty in the case of an accident -Nothing should be attached to the seat or its straps (like binky clips, toys etc) -Wash per your manual -Rear face until absolute minimum of 2, it's their bone development that matters most -If you go see someone to help you install your seat make sure they are CPST (Child Passenger Safety Technician) -READ YOUR MANUAL) The group Car seat Safety on Facebook is extremely helpful ... show more
Reviewed in the United States on July 16, 2025 by RaeMars23 RaeMars23
    • The only car seat brand we will ever buy for our kiddos! Only cons are the weight and width.
Style: One4Life Color: Eclipse Black
I have recommended this car seat to sooo many of my friends! If you have ever used the Click Tight system you know exactly why! This is the absolute easiest car seat to install/remove and you get the tightest installation EVER! I really love that the car seat is so sturdy and well built! There are so many safety features built in too! We upgraded to the One4Life with our last kiddo from the Advocate. One of the best features that I didn’t know I needed was the cup holders! I love that Britax added them onto this car seat! This car seat has so many pros! There are a few cons however in our opinion. The car seat is VERY heavy (which is great for safety but heavy to move). The other con is that it is very wide (again this is great for safety but we are not able to go 3 car seats wide in the backseat because of this). Even with these 2 cons we will never use another brand of car seat! ... show more
Reviewed in the United States on July 17, 2025 by Noël
    • The best carseat bar none
This is the most secure carseat that I’ve had! The clicktight option takes the seatbelt and pulls it taunt. This carseat won’t budge a millimeter even if pushed/pulled/shaken. Easy to set up. Heavier than other carseats but that is a good thing for structure.
Reviewed in the United States on October 12, 2025 by Bk
    • Highly recommend
Review Image by artzone artzone
I just purchased this car seat. First off How it looks: beautiful love the style comes in many colors and styles i did the one 4 life click tight ( it is actually true it installs tightly). Supper soft and easy to follow instructions. What features: well I purchase this for easy installation and it also looked very comfortable too when it arrived it had many cushions and air netting on the sides for to breath. Side button with one push and easy to adjust tilit It was easy to find the buttons all labeled side and under the seat. Pros: easy to read and understand, easy to adjust and installation was a breeze. Once installed correctly it dosent move at all very impressive as I have had many car seats and they always move a little even once installed correctly this one was zero movement highly recommend for safty. Con well I don't really have any yet it is so far everything I hoped for. So weight: well it is on the more heavier side but it's not any heavier than Carring a baby carrier with base. It is solid to carry and solid once buckled. Other qualities it also is approved for other transport such as a plan if you wish to fly. What I love is the tilt feature and how it grows with your child, easy to install and read direction on the car seat visible and it is in two languages. The cushions for the head is very comfortable. Highly recommend for baby on up however I already pass the baby stage carrier and purchase this after my child was already one. It can even use for infants up to 10 years old Again highly recommend ... show more
Reviewed in the United States on February 21, 2025 by artzone artzone
    • Yup, Buy it!
Style: One4Life Color: Iris Onyx
Very happy with this carseat! This is the 3rd one we've bought. We purchased and returned two as they felt cheaply made, unsafe and we didn't like the fit as well as how much they moved around after being tightly installed. This one is the exact opposite! It feels incredibly well made and safe, it doesn't budge from its position tightened down in the car, our 8 month old fits great in it and I'm happy with the amount of padding around the head. Great quality, great fit, durable, manufacturer takes the safety of your child seriously! Highly recommend! ... show more
Reviewed in the United States on April 23, 2025 by Katie
    • With every penny!
LOVE LOVE LOVE! Installs in seconds. No need to spend forever tightening car anchors or straps. Easy to clean and comfortable. Love that the cup holders can be removed for easy clean up. Super convenient to move from one car to another.
Reviewed in the United States on October 24, 2025 by Nicole A
    • Great seat, but cup holders are an issue
The seat itself is sturdy, safe, and comfortable, but my two-year-old can easily pull out the removable cup holders. I’ve already lost one, and when the cups aren’t in place, food and crumbs collect in the empty slots. Cleaning it out means taking the whole seat out of the car, flipping it over, and shaking it — not very convenient. ... show more
Reviewed in the United States on August 15, 2025 by Woodsman3000
    • Favorite car seat for my (soon to be) three kids!
Style: One4Life Color: Onyx Stone
We’ve bought five of these because it is our favorite car seat. I’ve also recommended it to at least three friends. They are so easy to install and the kids are comfortable in them. I really like that the rear facing weight limit is so high because I plan to keep my kids rear facing as long as I can. My one complaint is that the cup holders pop off easily, but in the grand scheme that isn’t that big of an issue. Will continue to buy these as we have more kids! ... show more
Reviewed in the United States on May 31, 2025 by Mimie Hull

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