Does the ibiyaya JetPaw Expandable Backpack fit Southwest Airlines?

No — the ibiyaya JetPaw Expandable Backpack (18 × 12 × 12 in) does not fit Southwest Airlines's 18.5 × 13.5 × 8.5 in under-seat limit.

18 × 12 × 12 in external

Too tall (12" > 8.5") against Southwest Airlines's 18.5 × 13.5 × 8.5 in limit

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12" tall exceeds the 8.5" limit by 3.5" and this carrier doesn't compress.

Last verified 2026-07-23 · matched to the published Southwest Airlines limit. Every fit is against the published maximum; real under-seat space varies by aircraft (why).

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