Radian 3QXT › fit in › Subaru Legacy

Will the Diono Radian 3QXT fit in a 2015–2024 Subaru Legacy?

Yes — the Diono Radian 3QXT fits a 2015–2024 Subaru Legacy.
The Radian 3QXT is about 17" wide; the Legacy's usable rear bench is about 50". It fits one rear position comfortably. Three across is tight (51" needed vs 50").

17"Radian 3QXT width

50"Legacy rear bench

Tightthree across

★★★☆☆NHTSA Ease-of-Use

Check the Radian 3QXT on Amazon → All seats for a Legacy

🔗 Amazon link is an affiliate link. As an Amazon Associate we earn from qualifying purchases — at no extra cost to you.

What fits this Legacy

One seat, rear position: Yes. The Radian 3QXT installs in an outboard rear position of a 2015–2024 Subaru Legacy with room to spare.
Three across: Tight — three need ~51" against only ~50". A narrower seat is the better bet.
Modes this seat covers: rear-facing → forward-facing → booster.
LATCH: lower anchors up to 40 lb; the Legacy has 2 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 Radian 3QXT's width (Diono published spec (17 in)) and the Legacy's rear-bench width (Typical for midsize car — approximate, verify install in your vehicle) are both approximate — confirm with a test-fit before buying.

Common questions

Will the Diono Radian 3QXT fit in a 2015–2024 Subaru Legacy?

Yes — the Diono Radian 3QXT (17" wide) fits a single rear seating position in a 2015–2024 Subaru Legacy. Three across is tight — its rear bench is about 50" and three of these would need 51".

Can you fit three Radian 3QXTs across a Legacy?

Probably not — three Radian 3QXTs need about 51" but the Legacy's usable bench is only about 50". Consider a narrower seat — see our narrowest-seats guide.

Sources: seat ratings & modes — NHTSA (pulled 2026-06-18); 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.