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How Do Car Seats Fit in a 2021 Lexus IS 350?

lexus is 350 2021 08 angle  blue  exterior  rear jpg 2021 Lexus IS 350 | photo

The verdict: Lexus updated its entry-level sports sedan for 2021, and the IS 300 and IS 350 get more muscular styling as well as an updated multimedia system that should be easier to use than the outgoing version. Also in the easy column are the sedan’s lower Latch anchors, which are exposed for quick connection. Unfortunately, insufficient rear legroom prevented the IS from earning top grades. 

Does it fit three car seats? No.

Take a look at how the Latch system and each car seat scored below in our Car Seat Check of the 2021 Lexus IS 350. 

Related: Search Car Seat Checks

lexus is 350 2021 csc scorecard png graphic

A Grade

  • Latch: The two sets of anchors sit under a large flap, and they’re exposed and easy to use once the flap is uncovered. 
  • Forward-facing convertible: Installation with the lower anchors was easy. Unless the convertible car seat’s adjustable back is set to its lowest position, you’ll need to raise the sedan’s head restraint to fit the seat flush against the seatback. Three top tether anchors sit on the rear shelf, and they’re clearly marked for easy connections. 

B Grade

  • Booster: After raising the head restraint to situate the booster flush against the seatback, it fit well. However, the bolstered seats push the booster on top of the buckle, complicating access. The sedan’s outboard buckles have stable bases, but the middle one is floppy, so kids will likely struggle connecting to that one independently. 

C Grade

  • Infant seat: This seat was easy to install, but to create enough clearance, we had to move the front seat forward enough that our 5-foot-6-inch passenger’s knees touched the glove box. 
  • Rear-facing convertible: Again, installation was trouble free, but front-passenger legroom was a problem. 

Grading Scale

A: Plenty of room for the car seat and the child; doesn’t impact driver or front passenger legroom. Easy to find and connect to Latch and tether anchors. No fit issues involving head restraint or seat contouring. Easy access to the third row.

B: One room, fit or connection issue. Some problems accessing the third row when available.

C: Marginal room plus one fit or connection issue. Difficult to access the third row when available.

D: Insufficient room, plus multiple fit or connection issues.

F: Does not fit or is unsafe.

About’s Car Seat Checks

Editors Jennifer Geiger and Jennifer Newman are certified child safety seat installation technicians.

For the Car Seat Check, we use a Chicco KeyFit 30 infant-safety seat, a Graco Contender 65 convertible seat and Graco TurboBooster seat. The front seats are adjusted for a 6-foot driver and a shorter passenger. The three child seats are installed in the second row. The booster seat sits behind the driver’s seat, and the infant and convertible seats are installed behind the front passenger seat.

We also install the forward-facing convertible in the second row’s middle seat with the booster and infant seat in the outboard seats to see if three car seats will fit; a child sitting in the booster seat must be able to reach the seat belt buckle. If there’s a third row, we install the booster seat and a forward-facing convertible. Learn more about how we conduct our Car Seat Checks.

Parents should also remember that they can use the Latch system or a seat belt to install a car seat, and that Latch anchors have a weight limit of 65 pounds, including the weight of the child and the weight of the seat itself.’s Editorial department is your source for automotive news and reviews. In line with’s long-standing ethics policy, editors and reviewers don’t accept gifts or free trips from automakers. The Editorial department is independent of’s advertising, sales and sponsored content departments.

Photo of Jennifer Geiger
News Editor Jennifer Geiger joined the automotive industry in 2003, much to the delight of her Corvette-obsessed dad. Jennifer is an expert reviewer, certified car-seat technician and mom of three. She wears a lot of hats — many of them while driving a minivan. Email Jennifer Geiger

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