Woah there, it looks like your browser is out of date.

To get the best experience, please update your browser.

Britax Marathon 70-G3 Convertible Car Seat

Britax Marathon 70-G3 Convertible Car Seat

BY BRITAX #5 in Car Seats

4.8 out of 5 stars
  • 5 Stars92%
  • 4 Stars6%
  • 3 Stars1%
  • 2 Stars1%
  • 1 Star0%
4.89 / 5 based on 151 Reviews

Product Description

Minimize Forward Movement in Crashes The Britax Marathon 70-G3 convertible car seat accommodates children rear facing from 5 to 40 pounds and forward facing from 20 to 70 pounds.  The Marathon 70-G3 is purposefully designed and engineered to minimize the forward movement of your child s head during a frontal impact to reduce the risk of head injury with the following revolutionary Britax head safety technologies: Base with SafeCell Technology designed to compress in a crash, significantly lowering the center of gravity and counteracting the forward rotation of the child seat. Integrated Steel Bars strengthen the connection to the vehicle and reduce forward flexing of the. see more...

Top Questions See all 91 Q&A

Britax Marathon 70-G3 Convertible Car Seat
Britax Marathon 70-G3 Convertible Car Seat
Reviews (151)
Q&A (21)
Leave a Review
REVIEWS
PRODUCT HIGHLIGHTS
  • "I wish I knew a little more about car seats when I bought it as I didn't realize that it wasn't meant for taller children as they outgrow it rear facing quickly." in 13 reviews
  • "love this car seat especially the print and that it is very safe has lots of padding and is very comfortable " in 9 reviews
  • "It's easy to install, is heavy duty, and makes me feel comfortable putting my son in it because of the high safety ratings! " in 5 reviews
  • "My 3 year old is still rear facing comfortably in this seat :) It's comfortable, easy to install and has so many added safety features." in 4 reviews
Ashley W.
Tifton, Ga
148 reviews
Mega Parent Expert Level 3
After our little one outgrew her infant seat we were in the market for a SAFE convertible seat. After much research and consulting the consumer reports we chose this seat and couldn’t be more pleased. It was on the pricey end but we have no regrets.
Amanda G.
murray, KY
197 reviews
best car seat ever. they ha E wonderful safety rating and get good rating with Co sumer reports. they are very cushioned and soft for baby. I love that they come withe the soft belly pad and soft strap covers. you can get the cutest covers as well. you won't be disappointed. I loved knowing how safe my bundle of joy was in her britax
Raegan Q.
16 reviews
purchased after my son & I were in a car accident. I love this seat. Pattern is cute. Easy to install. My son will be 3 in March and is still rear facing. Safety first! I did a ton of research before purchasing and would by again in a heartbeat!
Danielle K.
Michigan City , IN
106 reviews
I received one as a gift and it has been a blessing. I did some comparing to others and am very pleased with this one. My daughter is totally comfortable facing backwards in this chair. It is somewhat bulky so we leave it in our car but it's not a big deal to get it out and get it back in. Would definitely recommend!!
Samantha  R.
533 reviews
Mega Parent Expert Level 4
Very cute car seat! Love the pattern and so does my boy. A bit pricey but it's a very good car seat and is very safe. Definitely recommend to any one who is in search of a car seat that they want to keep their babies safe in
Jenn G.
Atascadero, CA
861 reviews
Mega Parent Expert Level 4
We have used this through two kids now and it’s still just as good as the day we got it! A little pricey but not bad for the quality. Cute cowhide print too. Only downside is that it’s HEAVY. Thankfully we don’t have to move it from car to car otherwise I would have gotten a lighter weight seat.
alysse h.
San Antonio, TX
45 reviews
Absolutely love this carseat. My daughter fits so comfortably and seems to enjoy being out of the infant carseat. I love that it is top rated in safety, which was the most important factor in our purchase. Price was was fair and I would definitely recommend to any other parent.
Ashleigh F.
Douglasville , GA
251 reviews
Mega Parent Expert Level 2
This is a super cute car seat , and has many great reviews , but please make sure you read the height and weight requirements , as I didn't do so, and ended up happening to take y back in exchange for the right one for my daughter
Amanda J.
Los Angeles, CA
8 reviews
We bought this car seat because my little one was growing out of his infant seat which we loved. I did a lot of research on car seat.org and consumer reports and decided this car seat was the one for us. Firstly I drive a jeep wrangler and this car seat was said to have a small footprint, meaning you could put it behind the passenger seat, and the passenger could still sit *relatively* comfortably. The ease of installation was also a plus. We were coming from the Chicco Keyfit 30 which had glowing reviews for ease of installation and I was dreading moving up to a convertible. I will say its not AS EASY as the KeyFit 30. But neither is anything else on the market. Additionally it has some of the THE HIGHEST safety reviews on Consumer Reports being out many larger and therefore theoretically "safer" convertible car seats. I am immensely happy with this purchase and even convinced my husband to purchase the same seat for his car. Love love love!
Shelly B.
Miami, FL
9 reviews
Before my son was born I did countless hours of research into car seats. I really wanted to spend my money wisely and buy a safe and top quality seat that I would feel good about putting my son into. I chose the Brixax Marathon seat and I am still happy with my decision 3 years later.
This seat is made for infants as well as toddlers and small children. When my son was first born we purchased in insert that kept his head securely in place and when he had more neck control we were able to put him directly in the seat. I haven't had an accident so I can't tell you how the seat would hold up based on experience, but I am happy with the quality of the seat. I have traveled with this seat and it is airplane approved as well.. always good to know. And after many many washes the cover has held up good and looks great.
Martha A.
Ramona , CA
129 reviews
At what age did you forward face your little ones?
Kathie M.
Maricopa, AZ
56 reviews
Will this totally ruin your leather? We are looking for a good car seat but worries about ruining our leather in our car.
Jelena K.
Jersey Vlg, TX
110 reviews
Can you use this rear facing for a newborn?
Laura W.
Vancouver, WA
27 reviews
How heavy is this seat and is it easy to hook in?
Yesi C.
Fallon, NV
14 reviews
Does this car seat take up a lot of space? And is pretty pricy?

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Sign up now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Sign up now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Sign up now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Join now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Join now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Join now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Sign up now

JOIN NOW to gain access to over 25 million product reviews, free full size samples, and the latest product news.

Sign up now

Sign up to join our community!