In-cabin pet carriers that fit Porter Airlines

The carriers from our list that clear Porter Airlines's official 21.5 × 15.5 × 10.5 in under-seat limit — sorted best-fit first, with the ones that squeeze in when collapsed flagged.

Last verified 2026-08-14 · matched to the published Porter Airlines limit

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Carrier	Size	Fit	Buy
Sherpa Original Deluxe (Small) 15 × 10 × 8.5 in is within 21.5 × 15.5 × 10.5 in — 6.5" spare on length, 5.5" on width, 2" on height. · collapsible/flex	15 × 10 × 8.5 in	Fits	See on Amazon →
Mr. Peanut's Gold Series Mini (Low-Profile) 16 × 10.5 × 9.8 in is within 21.5 × 15.5 × 10.5 in — 5.5" spare on length, 5" on width, 0.7" on height. · collapsible/flex	16 × 10.5 × 9.8 in	Fits	See on Amazon →
Petmate Soft-Sided Kennel Cab (Small) 17 × 10 × 10 in is within 21.5 × 15.5 × 10.5 in — 4.5" spare on length, 5.5" on width, 0.5" on height. Tightest margin is 0.5", so measure before you fly.	17 × 10 × 10 in	Fits	See on Amazon →
Sherpa Original Deluxe (Medium) 17 × 11 × 10.5 in is within 21.5 × 15.5 × 10.5 in — 4.5" spare on length, 4.5" on width, 0" on height. Tightest margin is 0", so measure before you fly. · collapsible/flex	17 × 11 × 10.5 in	Fits	See on Amazon →
Diggs Passenger 17 × 12 × 10.5 in is within 21.5 × 15.5 × 10.5 in — 4.5" spare on length, 3.5" on width, 0" on height. Tightest margin is 0", so measure before you fly.	17 × 12 × 10.5 in	Fits	See on Amazon →
Sleepypod Atom 17 × 8.5 × 10.5 in is within 21.5 × 15.5 × 10.5 in — 4.5" spare on length, 7" on width, 0" on height. Tightest margin is 0", so measure before you fly.	17 × 8.5 × 10.5 in	Fits	See on Amazon →
Sleepypod Air Collapses from 22" to ~16" long, which fits — height 10.5" is within 10.5". · collapsible/flex	22 × 10.5 × 10.5 in	Fits collapsed	See on Amazon →
Sherpa Original Deluxe (Large) 11.5" tall vs a 10.5" limit — 1" over, but the flexible-height top compresses down. Verify it squeezes under your actual seat. · collapsible/flex	19 × 11.75 × 11.5 in	Flexes — check height	See on Amazon →
Mr. Peanut's Gold Series Standard (Expandable) 11.5" tall vs a 10.5" limit — 1" over, but the flexible-height top compresses down. Verify it squeezes under your actual seat. · collapsible/flex	18.5 × 11.75 × 11.5 in	Flexes — check height	See on Amazon →
SturdiBag Pro (Large, Flexible Height) 11.5" tall vs a 10.5" limit — 1" over, but the flexible-height top compresses down. Verify it squeezes under your actual seat. · collapsible/flex	18 × 11.5 × 11.5 in	Flexes — check height	See on Amazon →

Every fit is against the published maximum; real under-seat space varies by aircraft (why). Full rules & fees: Porter Airlines pet policy →

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