Does the SturdiBag Pro (Large, Flexible Height) fit Southwest Airlines?

No — the SturdiBag Pro (Large, Flexible Height) (18 × 11.5 × 11.5 in) does not fit Southwest Airlines's 18 × 10.5 × 10 in under-seat limit.

SturdiBag publishes no pet-size limit for this carrier. The 18 × 11.5 × 11.5 in above is what Southwest Airlines measures, not the room your pet gets — measure your pet lying down before you buy. How →

18 × 11.5 × 11.5 in external

Too big against Southwest Airlines's 18 × 10.5 × 10 in limit

Not available on Amazon right nowIn stock and fits the same airlines: Petmate Soft-Sided Kennel Cab (Medium)

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18 × 11.5 × 11.5 in is over the 18 × 10.5 × 10 in limit.

Last verified 2026-09-24 · matched to the published Southwest Airlines limit. Every fit is against the published maximum; real under-seat space varies by aircraft (why).

Full Southwest Airlines shortlist: all carriers that fit Southwest Airlines → · this carrier on other airlines: SturdiBag Pro (Large, Flexible Height) specs → · Southwest Airlines rules & fees: Southwest Airlines pet policy →