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

No — the SturdiBag Pro (Large, Flexible Height) (18 × 11.5 × 11.5 in) does not fit United Airlines's 18 × 11 × 11 in under-seat limit.

SturdiBag publishes no pet-size limit for this carrier. The 18 × 11.5 × 11.5 in above is what United 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 United Airlines's 18 × 11 × 11 in limit

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18 × 11.5 × 11.5 in is over the 18 × 11 × 11 in limit.

Last verified 2026-09-23 · matched to the published United Airlines limit. Every fit is against the published maximum; real under-seat space varies by aircraft (why).

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