Knox › fit in › Toyota Sienna
Will the UPPAbaby Knox fit in a 2011–2020 Toyota Sienna?
Yes — the UPPAbaby Knox fits a 2011–2020 Toyota Sienna.
The Knox is about 18.8" wide; the Sienna's usable rear bench is about 54". It fits one rear position comfortably. Three across is tight (56.4" needed vs 54").
The Knox is about 18.8" wide; the Sienna's usable rear bench is about 54". It fits one rear position comfortably. Three across is tight (56.4" needed vs 54").
18.8"Knox width
54"Sienna rear bench
Tightthree across
★★★☆☆NHTSA Ease-of-Use
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What fits this Sienna
- One seat, rear position: Yes. The Knox installs in an outboard rear position of a 2011–2020 Toyota Sienna with room to spare.
- Three across: Tight — three need ~56.4" against only ~54". A narrower seat is the better bet.
- Modes this seat covers: rear-facing → forward-facing.
- LATCH: lower anchors up to 35 lb; the Sienna has 3 lower-anchor positions.
ℹ️ Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip. The Knox's width (UPPAbaby published spec (23.8"L x 18.8"W x 27.4-32.5"H); independent review measured 18.6 in, closely matching) and the Sienna's rear-bench width (Toyota dimensions + owner measurements (approx)) are both approximate — confirm with a test-fit before buying.
Common questions
Will the UPPAbaby Knox fit in a 2011–2020 Toyota Sienna?
Yes — the UPPAbaby Knox (18.8" wide) fits a single rear seating position in a 2011–2020 Toyota Sienna. Three across is tight — its rear bench is about 54" and three of these would need 56.4".
Can you fit three Knoxs across a Sienna?
Probably not — three Knoxs need about 56.4" but the Sienna's usable bench is only about 54". Consider a narrower seat — see our narrowest-seats guide.
Sources: seat ratings & modes — NHTSA (pulled 2026-10-13); dimensions — manufacturer specs and owner measurements. Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip.