3 Across Installations: Which Car Seats Will Fit In a Mazda 3?

The Mazda 3 (known in Japan as the Mazda Axela) is one of the fastest-growing small cars in the United States today, providing a stylish counterpart to more established models like the Honda Civic, Toyota Corolla, Ford Focus, and Toyota Prius, while competing directly with newer models like the Chevy Cruze, Hyundai Elantra, and Kia Forte. Its distinctive looks and marketing toward young professionals have made it a popular choice among small families interested in safe transportation without sacrificing style. I borrowed a few models this past weekend to see which car seats fit well in a Mazda 3, and in particular, to look at which car seats fit well in 3 across combinations in the Mazda 3.

However, before looking at the seat combinations, let’s review best practice principles when it comes to car seat safety. For me, that means rear-facing children as long as possible (ideally until 4!), and then forward-facing our kiddos as long as feasible (ideally until 8!), and then placing them in booster seats until they’re capable of using a regular seat belt (which typically happens between 10 and 12). These guidelines are meant to keep our little ones as safe as possible by restraining them appropriately as long as feasible.

That said, if you’re going to use best practices, it helps to know which seats will and won’t work in the Mazda 3, which is why I put this guide together. I got out a lot of car seats and after several hours and bruised knuckles, have what I believe is the most complete list of 3 across combinations possible in the Mazda 3.  If you find the list helpful when shopping for car seats, you can shop through my Amazon link below. I’ll add more seats as I test them over time.

You can access the complete 3 across guide for every vehicle here and the complete list of recommended seats here. The Canadian car seat guide is here. 3 across car seat images are courtesy of Wikipedia.

mazda 3 - axela - publicdomain2014, 2015, 2016, 2017 Mazda 3 (BM)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Diono Radian RXT (x3).

Diono Radian R120 (x3).

Diono Radian R100 (x3).

Chicco KeyFit 30 (x3).

Clek Oobr (x3).

Combi Coccoro (x3).

Britax Frontier 90, Britax Advocate ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4, Britax Frontier 90.

Britax Frontier 90, Britax Marathon ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4, Britax Frontier 90.

Tips and Tricks:

This generation of the Mazda 3 is 180 inches long and 71 inches wide, which means you’ll gain an inch in width over the previous generation, although you also lose an inch in length. You’ll still definitely need seat belt installations to have a chance of getting the Britax seats to puzzle well together, but it’s possible to do so with enough time and effort.

As with most small cars, you’ll also face a challenge in front-to-back space due to the short length of the 3. You’ll want to check out the front-to-back convertible leg room guide if you’ve got taller drivers or front-seat passengers.

10mazda32010, 2011, 2012, 2013 Mazda 3 (BL)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Combi Cocorro (x3).

Diono Radian / RXT (x3).

Britax Frontier 90, Britax Advocate ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4, Britax Frontier 90.

Britax Frontier 90, Britax Marathon ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4, Britax Frontier 90.

Tips and Tricks:

This generation of the Mazda 3 is 181 inches long and 69 inches wide, which means that any seats that work in the prior generation can be expected to work in this generation as well, and that you’ll have a bit more front-to-back room too, which is always enjoyable if you’re sitting in the front seats. You’ll want to check out the front-to-back convertible leg room guide if you’ve got taller drivers or front-seat passengers.

08mazda32004, 2005, 2006, 2007, 2008, 2009 Mazda 3 (BK)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Combi Cocorro (x3).

Diono Radian / RXT (x3).

Britax Frontier 90, Britax Advocate ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Advocate G4, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Boulevard G4, Britax Frontier 90.

Britax Frontier 90, Britax Marathon ClickTight, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4.1, Britax Frontier 90.

Britax Frontier 90, Britax Marathon G4, Britax Frontier 90.

Tips and Tricks:

This initial generation of the Mazda 3 is 178 inches long and 69 inches wide, which makes it more challenging than the average car when it comes to puzzling a successful 3 across installation. However, with a bit of creativity, luck, and seat belt installations, you can still make several seats work.

In the Frontier-Advocate / Boulevard-Frontier installations, the outboard seats will likely tilt slightly inward once the installations are complete, due to how the outboard seats in the 3 are organized. However, it’s still a safe installation since the seats are independently tight and do not overlap each other.

If you find the information on car safety, recommended car seats, and car seat reviews on this car seat blog helpful, you can shop through this Amazon link for any purchases, car seat-related or not. Canadians can shop through this link for Canadian purchases.

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