2024 Toyota Sienna

The 2024 Toyota Sienna is a hybrid-only minivan that can fit families of 7 or 8, but not without some car seat challenges. There is a lot of flexibility with placement of lower anchors and tether anchors, but the small center seat and third row seat cut-outs are limiting. The third row is not three-across-friendly for three harnessed car seats. 

There are also very specific rules about the seatback recline angle when installing car seats. Refer to your owners manual for guidance and note that the second and third row are different.

LATCH

In the second row, there is a full set of LATCH (lower anchors and tether anchor) in every seating position. 

The third row includes a full set of LATCH in the outboard positions. But then the center seat has a tether anchor and only one lower anchor. 

That single lower anchor for 3C is designed to pair with a single lower anchor from 3D which makes one standard-spaced (11”) lower anchor set. However, if you use LATCH in 3C that renders 3D unusable for any occupant due to belt overlap.

The lower anchors are accessible and not deeply buried in the seat bight, which makes installation easier even for frequent seat swaps or baseless installs.

Belt Buckles

The seat belt buckles in the second row are upright and accessible. They can flex on their hinges up and down depending on your car seat installation. The second row center seat’s buckle is partially overlapped with the lower anchors, limiting booster use with LATCH - though booster use is dramatically limited regardless due to the narrow seating width.

In the third row, the buckles are rigid and recessed in 3D and 3C. They may be harder to access when car seats or boosters are installed which can impact independent buckling for older kids. 3P’s buckle is able to flex up and down like the second row buckles. 

Seat Shape

The Sienna’s second row center seat is extremely narrow and more shallow than the outboard seats. While three across is possible with the right seats, it’s not easy. 

The third row outboard seats are contoured so the front outside edges of the seats have less depth than the inside edges do. This contributes to overhang for almost all car seats and boosters. Verify if your seat has overhang or not. If it does, make sure it’s permitted in your car seat’s manual. 

The third row center seat is a normal depth but is narrow so car seat selection is limited here as well. 

Head Restraints

The head restraints are adjustable and removable in the second row. The third row outboard head restraints are not removable or adjustable. They are flush and do not protrude forward, so they don’t end up causing a gap for many car seats. 

Forward-facing car seats and boosters may achieve a more flush installation when head restraints are adjusted or removed (if permitted by the vehicle manual). Most booster seats do not allow a gap caused by head restraints, so positioning should be checked carefully for each seating location.

Three Across Considerations

For a minivan, three across is particularly challenging. If three across with sliding doors is your goal, I’d look elsewhere. If you already own the Sienna, there are combinations to make it work!

In most cases, seats will need to be 17–18 inches wide or less, but successful combinations depend more on seat shape than width alone.

The center seat is best suited for infant seats or narrow convertibles with compact bases. 

Good options include:

Britax Poplar (has side overhang, but the “runners” or feet underneath the base, make contact with the vehicle seat)
Graco SlimFit3 LX (True3Fit)
Chicco Fit3X
Evenflo All4Stages Slim Plus Canopy

For a booster option, the Peg Viaggio Flex 120 fits snugly here too (as does booster mode of the all-in-one car seats listed above.)

For the third row, three of the ultra narrow Graco SlimFit3 LX 3 in 1 car seats did not install without significant overhang in 3D. If you need to fit three children in the back, the Ride Safer Travel Vest may be the only option for some set-ups. A narrow backless booster seat like the Cosco Rise gives more flexibility than a harnessed car seat. 

If you’re attempting a three-across setup, it’s often easiest to install the center seat first, followed by the outboard seats. Always verify each seat is independently tight (moves less than 1” at the belt path even when adjacent seats are removed).

Rear-Facing and Legroom

The Sienna offers excellent rear passenger space, especially in the second row. The second row sits on tracks that can move all the way forward or back, right up against the third row. If you don’t have third row passengers and need the space, you have it! If you plan to have both second and third row passengers, there is ample legroom to still fit a compact rear-facing seat in the third row and a bulkier, rotating seat in the second row. 

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