3 Across Installations: Which Car Seats Will Fit in a Toyota Prius?

The Toyota Prius is easily the most popular hybrid vehicle in the United States, and is chosen by millions of families around the United States as a safe and efficient way to transport their families. In the hybrid market, it has few competitors; only the now-defunct Honda Insight and Chevrolet Volt are on the map in the small car category, and neither offers the reliability of the Prius.

As a result, it’s no surprise fuel- and environment-conscious families look to the Prius to get their kids from point A to B. However, in order to transport multiple children, you need to know which car seats fit well next to each other and which ones don’t. If you’ve got 3 kids, you also need to keep in mind which seats will fit 3 across in a Toyota Prius. That’s what this guide is designed to help you figure out.

First of all, I always like to begin with the basics of best practices in car seat safety. These suggestions are based on research on the kinds of crash forces children face at different ages and in different kinds of car seats (harnessed seats, booster seats, forward-facing, rear-facing, etc). The research is rather clear: rear-face as long as possible (ideally until 4!), and then forward-face as long as possible (ideally until 6, 7, or 8!), and then booster until a regular belt fits your child (which typically happens between 10 and 12). Keeping your kids in safer configurations for as long as possible increases their odds of surviving collisions of all kinds.

However, for this information to be helpful, you need to know if a particular car seat will fit in your particular vehicle. Here are my experiences fitting a range of seats inside various years of the Toyota Prius. I’ll periodically update each page as I try more seats in more positions.

I have archived the complete 3 across guide for every vehicle here and the complete list of recommended seats here. Canadians can view recommended seats here. 3 across car seat images are courtesy of Wikipedia.

2016, 2017, 2018 Toyota Prius (XW50)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Chicco KeyFit 30 (x3).

Diono Radian RXT (x3).

Diono Radian R120 (x3).

Diono Radian R100 (x3).

Combi Coccoro (x3).

Clek Fllo, Diono Radian / RXT, Diono Radian / RXT.

Chicco KeyFit 30Clek Fllo, Chicco KeyFit 30.

Harmony Youth Booster, Diono Radian / RXT, Harmony Youth Booster.

Britax Parkway SGL, Harmony Youth Booster, Diono Radian / RXT.

Diono Radian / RXT, Diono Radian / RXT, Britax Parkway SGL.

Britax Boulevard / Marathon, Harmony Youth Booster, Diono Radian / RXT.

Tips and Tricks:

The current generation of the Prius is just under 179 inches long and just over 69 inches wide, which means, practically speaking, your 3 across possibilities aren’t going to change from the previous generation. You technically have a shade more front-to-back room, but it isn’t going to make a significant difference in comfort; you’ll still want to use angle adjusters if you’re rear-facing with Radians, for example. You’ll definitely still want to use seat belts with all 3 seats; the back row is too narrow to make LATCH practical or even feasible with 3 seats.

prius - 2010 - publicdomain2010, 2011, 2012, 2013, 2014, 2015 Toyota Prius (XW30)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Chicco KeyFit 30 (x3).

Diono Radian RXT (x3).

Diono Radian R120 (x3).

Diono Radian R100 (x3).

Combi Coccoro (x3).

Clek Fllo, Diono Radian / RXT, Diono Radian / RXT.

Chicco KeyFit 30Clek Fllo, Chicco KeyFit 30.

Harmony Youth Booster, Diono Radian / RXT, Harmony Youth Booster.

Britax Parkway SGL, Harmony Youth Booster, Diono Radian / RXT.

Diono Radian / RXT, Diono Radian / RXT, Britax Parkway SGL.

Britax Boulevard / Marathon, Harmony Youth Booster, Diono Radian / RXT

Tips and Tricks:

The 2010-2015 generation of the Prius is 176 inches long and 69 inches wide, which is 1 inch longer and 1 inch wider than the previous generation. As a result, it will be slightly easier to 3 across in this generation than in the previous, although it will still be a challenge with a number of installations. As usual, when dealing with vehicles this narrow internally, you’ll need to use seat belts from the start; don’t even bother with the LATCH anchors, as they aren’t nearly as efficient with the limited space you’ve got.

prius - 2008 - publicdomain2004, 2005, 2006, 2007, 2008, 2009 Toyota Prius  (XW20)

Guaranteed 3 across installations:

Clek Fllo (x3).

Clek Foonf (x3).

Chicco KeyFit 30 (x3).

Diono Radian RXT (x3).

Diono Radian R120 (x3).

Diono Radian R100 (x3).

Combi Coccoro (x3).

Clek Fllo, Diono Radian / RXT, Diono Radian / RXT.

Tips and Tricks:

The second generation of the Toyota Prius is 175 inches long and 68 inches wide, which means you’re going to struggle with 3 across installations unless dealing with particularly narrow seats, such as the Fllos, Foonfs, and Radians I mention above. However, there are probably other seats you might be able to squeeze in between those seats with a bit of patience and elbow grease. Remember to use the seat belts instead of LATCH to increase your odds of successful installations.

If you find the information on car safety, recommended car seats, and car seat reviews on this car seat blog helpful, you can bookmark and shop through this Amazon link. Canadians can bookmark and shop through this link.

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