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Britax Marathon vs Boulevard – What is the Difference?

My Choice: The Britax Marathon

Britax features four convertible car seat options: the Advocate, Boulevard, Marathon, and Roundabout. The Advocate is the most expensive, and the Roundabout is the least expensive. In the middle, they have the Boulevard and the Marathon, which are surprisingly similar, with the Boulevard having just a few extra features. So, is it worth it to opt for the Boulevard over the Marathon?

Image of Britax Marathon ClickTight Convertible Car Seat - 1 Layer Impact Protection, Verve

Image of the Britax Boulevard G4.1 Convertible Car Seat, OnyxHonestly, no.

The Boulevard features an additional layer of side impact protection, but comes at a much higher cost considering this one difference. Because both car seats also come in a Clicktight option, I say it is best to get the Marathon with Clicktight over Boulevard without Clicktight (they are almost identical in cost). The additional indirect safety that you get from the Clicktight feature is better than the additional layer of side impact protection on the Boulevard, in my opinion.

That being said, I have nothing against the Boulevard or Boulevard with Clicktight. If it fits in your budget, then definitely go for it! There are no downfalls of the Boulevard over the Marathon besides the additional cost.

UPDATE: Britax recently discontinued the regular versions of both the Marathon and Boulevard. Because the ClickTight option was so great, now you can find only the Boulevard ClickTight and the Marathon ClickTight. But keep reading to see the big similarities and differences between these two models.

How are they the same?


Both the Marathon without Clicktight and Boulevard without Clicktight have the following weight and height limits:

  • Child Weight – Rear Facing:   5 – 40 lbs
  • Child Weight – Forward Facing:   20 – 65 lbs*
  • Child Standing Height:   49″ or less
  • Child Seated Shoulder Height – Rear Facing:   9 – 16.75″
  • Child Seated Shoulder Height – Forward Facing:   12 – 16.75″

The Marathon with Clicktight and the Boulevard with Clicktight have even broader seated shoulder height limits:

  • Child Seated Shoulder Height Rear-Facing:   7.6 – 18.65″
  • Child Seated Shoulder Height Forward-Facing:   12 – 18.65″

Both have Clicktight option

Britax’s Clicktight feature allows for quick and easy installation of your car seat. You simply lift the front of the car seat, feed the seat belt through, and click the front of the seat closed. It ensures a tight installation, so that you don’t have to fuss with tightening the seat belt yourself (which, if you have ever had to do, you know can be tough!)

While this feature doesn’t necessarily provide additional protection in the event of an accident, it does help to ensure your car seat is installed correctly. That being said, you shouldn’t rely solely on Clicktight to ensure a proper installation. Make sure to read the directions thoroughly, and have your car seat installation inspected! While Clicktight helps to ensure a correct installation, it won’t do all the work for you.

Both have Anti-Rebound Bar (ARB) option

Image of the Britax Marathon ClickTight ARB Convertible Car Seat, Vue

The Anti-Rebound Bar is a new feature through Britax. It helps to stabilize the car seat when rear-facing, minimizing movement of the car seat if an accident were to occur.

Both the Clicktight and Anti-Rebound Bar features come at an additional cost on the Boulevard and Marathon. While I definitely advocate for Clicktight, I don’t see the Anti-Rebound Bar as absolutely necessary.

Safe-Cell Impact Protection

Britax’s Safe-Cell impact protection consists of impact-absorbing materials to minimize forces transferred to your child in the event of an accident. Both the Boulevard and Marathon feature steel frames, a deep foam-lined shell, and an impact-absorbing base. These features make these seats incredibly safer than the baseline standard for car seats.

No re-thread harness

Image of the Britax USA Marathon ClickTight Convertible Car Seat, Verve

One of my favorite features that both the Boulevard and Marathon have is a quick-adjust harness. On many car seats, you need to fully take the harness out of the back of the car seat and re-thread it through in order to adjust the harness height. The Boulevard and Marathon feature a no re-thread harness, so with a quick squeeze and lift of the back of the car seat, your harness can be adjusted as your child grows. This way you don’t have to take the seat out of your car at all to reposition the harness.

Automatic level indicator

Image of the Britax USA Marathon ClickTight Convertible Car Seat, Verve

The Boulevard and Marathon both have multiple recline positions. Another one of my favorite features on these Britax seats is the automatic level indicator. It lets you know when the seat is at the right angle, based on your child’s age and whether they are rear-facing or forward-facing.

Easy remove cover

Both the Marathon and Boulevard have Britax’s easy to remove cover. What makes it easy to remove is that you don’t have to unthread the harness in order to take the cover off. Britax’s least expensive convertible seat, the Roundabout, is the only one on their line that does not feature this easy remove cover.

(Want to see how the Britax Roundabout compares to the Marathon? Check out my other review here!)

Product weight

I love both of these seats, but I think it is important to note that they are HEAVY. Especially if you go with the Clicktight option on either seat – the Clicktight feature adds about 10 pounds to the seat.

  • Marathon: 19.5 pounds
  • Marathon with Clicktight: 28.5 pounds
  • Boulevard: 19.5 pounds
  • Boulevard with Clicktight: 29.4 pounds

If you are looking for a seat to air travel with, you may want to consider another car seat, or an additional traveling car seat. These are no fun to have to lug around.

But, if you need a smaller car seat for twins or a compact vehicle, these are both pretty solid choices.

Installation Video

How are they different?

Side Impact Protection

The main difference between the Marathon and the Boulevard is that the Boulevard has an additional layer of side impact protection. This secondary layer of protection is in the form of additional head protection. This quick adjust head protection looks like a pillow essentially, and helps keep a child’s head in place in the event of an accident.

When looking at the Marathon and Boulevard, the additional layer of side impact protection is really the only difference. But there are differences when looking at the standard model vs the ClickTight model.

Clicktight option differences

Maximum seated height

Both the Boulevard Clicktight and the Marathon Clicktight have a higher maximum seated height than the models without Clicktight. The Boulevard Clicktight and Marathon Clicktight’s maximum seated height is 18.65 inches, whereas the standard version of both has a maximum seated height is 16.75 inches. This is because the Clicktight version has two additional harness slot positions, creating this wider range of seated height limits: the Clicktight has 14 harness slot positions, while the standard has 10.

How important is this?

Children usually reach the maximum height limit for their car seat before reaching the maximum weight limit. If your child is above average in height, or has a long torso, this extra 1.9 inches that the Clicktight option has could give them some extra time in a convertible seat before making the switch to a harness/booster seat. And it is best to keep them in each stage of car seat for as long as possible.

If your child isn’t especially tall, this extra 1.9 inches might not make too much of a difference. They may be ready to switch to the next car seat stage by the time they reach the maximum seated height on the Boulevard Clicktight or Marathon Clicktight.

Different patterns

When I pick out a car seat, I usually focus on safety features or height and weight limits, but it’s hard not to judge based on the available patterns! Both the Boulevard and Marathon have some fun patterns available. I personally like the Boulevard patterns better. I could see this swaying me in the direction of the Boulevard, but I’m sure there are others out there who would feel the same about the Marathon patterns! It’s all up to you, but it’s fun to check out while shopping around.

Other choices

See the top convertible car seat brands of this year here.

Different Colors

Color options for the Marathon

Image of the Britax Marathon ClickTight ARB Convertible Car Seat, Vue Image of the Britax USA Marathon ClickTight Convertible Car Seat, Oasis With EZ-Cling Sun Shades

Color options for the Boulevard

Image of the Britax Boulevard Convertible Car Seat Cover Set, Domino Image of the Britax Boulevard ClickTight Convertible Car Seat With Black Cup Holder, VectorImage of the Britax Boulevard Convertible Car Seat Cover Set, MosaicImage of the Britax Systems Boulevard ClickTight Convertible Car Seat with Cup Holder - Trek



Britax Marathon

  • 4.4 out of 5 stars, 177 reviews – Target.com
  • 4.5 out of 5 stars, 292 reviews – Walmart.com
  • 4.6 out of 5 stars, 294 reviews – Kohls.com

Britax Boulevard

  • 4.5 out of 5 stars, 203 reviews – Target.com
  • 4.5 out of 5 stars, 215 reviews – Babies “R” Us
  • 4.4 out of 5 stars, 209 reviews – Kohls.com

Ease of Use Ratings

When it comes to safety, installation and ease of use are incredibly important. While all car seats are required to pass federal safety testing, some are easier to use than others. The National Highway Traffic Safety Administration computes an ease of use rating for every car seat in several categories. See the ratings below.

Overall, the Britax Marathon Forward-facing received a rating of 5 stars.

NHTSA ease of use rating for the Britax Marathon ClickTightForward-Facing
Credit: NHTSA

The results below show that Britax Boulevard Rear-facing received a rating of 4 stars.

NHTSA ease of use rating for the Britax Boulevard ClickTightRear-Facing
Credit: NHTSA

My Recommendation

Personally, I think the Marathon provides sufficient protection, and it’s not worth paying the additional cost for the Boulevard. If the Boulevard had more additional features, I may think otherwise, but there the additional feature or two isn’t worth the additional cost in my opinion.  That being said, if you have a child who is above average height, I can see opting for the more expensive Boulevard because it may allow you to keep your child in a convertible seat for longer.

Especially if you are on a budget and deciding between these two, I would suggest using the extra money you would spend on the Boulevard and put it towards getting the Clicktight option Marathon. The Marathon Clicktight is about the same price as the Boulevard without Clicktight. Clicktight is a much better bang for your buck than the additional impact protection on the Boulevard.

Pamela Halstead

I am a stay at home mother to one son. With a background in safety and health, I am very safety-conscious, especially when it comes to products for my child!