Petsfit (Medium) Expandable Soft-Sided vs Sherpa Original Deluxe (Medium): which airline pet carrier?
Short answer: The Sherpa Original Deluxe (Medium) is within the published size limit of more airlines: 11 of the 58 that publish one, against 10 for the Petsfit (Medium) Expandable Soft-Sided. In the table, the Sherpa Original Deluxe (Medium) is amber for another 28 airlines: over the published size, so it would have to be collapsed, flexed or squeezed to go under the seat. Each amber row shows by how much.
Both carriers compared the way an airline sees them: by published size against each airline's under-seat limit. Petsfit (Medium) Expandable Soft-Sided is 17 × 11 × 11 in; Sherpa Original Deluxe (Medium) is 17 × 11 × 10.5 in.
Side by side
| Property | Petsfit (Medium) Expandable Soft-Sided | Sherpa Original Deluxe (Medium) |
|---|---|---|
| External size (L×W×H) | 17 × 11 × 11 in | 17 × 11 × 10.5 in |
| Type | soft-sided · expandable | soft-sided · flexible height |
| Pet weight | up to ~13 lb | up to ~16 lb |
| Airlines it fits outright | 10 of 58 | 11 of 58 |
Airline by airline
Green = within the published size; amber = fits only collapsed / flexed; grey = over. Height is strict — it's the dimension a seat won't negotiate on.
No airlines match.
| Airline | (Medium) Expandable Soft-Sided | Original Deluxe (Medium) |
|---|---|---|
| Aegean Airlines | Too big | Too big |
| Air Canada | Too tall (11" > 8") | Flexes — 2.5" over |
| Air Europa | Too big | Too big |
| Air France | Too tall (11" > 9.4") | Flexes — 1.1" over |
| Air Transat | Too big | Too big |
| airBaltic | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Alaska Airlines | Too tall (11" > 9.5") | Flexes — 1" over |
| Alaska Horizon (Horizon Air) | Too tall (11" > 9.5") | Flexes — 1" over |
| Allegiant Air | Exact fit | Fits |
| American Airlines | Exact fit | Exact fit |
| American Eagle (regional, incl. Republic Airways) | Exact fit | Exact fit |
| Asiana Airlines | Too tall (11" > 8.2") | Too tall (10.5" > 10.2" soft max) |
| Austrian Airlines | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Avelo Airlines | Too big | Too big |
| Avianca | Too tall (11" > 10") | Flexes — 0.5" over |
| Azul Linhas Aéreas | Too big | Too big |
| Breeze Airways | Too big | Too big |
| Brussels Airlines | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Cape Air | Too tall (11" > 8.5") | Flexes — 2" over |
| Condor | Too tall (11" > 9") | Flexes — 1.5" over |
| Contour Airlines | Too tall (11" > 10") | Flexes — 0.5" over |
| Copa Airlines | Exact fit | Exact fit |
| Delta Air Lines | Exact fit | Exact fit |
| Discover Airlines | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Edelweiss | Too tall (11" > 9.1") | Flexes — 1.4" over |
| EL AL Israel Airlines | Too big | Too big |
| Etihad Airways | Too big | Too big |
| Eurowings | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Finnair | Too tall (11" > 7.9") | Flexes — 2.6" over |
| Frontier Airlines | Exact fit | Fits |
| GOL Linhas Aéreas | Too big | Too big |
| Hawaiian Airlines | Too tall (11" > 9.5") | Flexes — 1" over |
| Iberia | Too tall (11" > 9.8") | Flexes — 0.7" over |
| ITA Airways | Too tall (11" > 9.1") | Flexes — 1.4" over |
| JetBlue | Too tall (11" > 8.5") | Flexes — 2" over |
| JSX | Exact fit | Exact fit |
| KLM Royal Dutch Airlines | Too tall (11" > 9.4") | Flexes — 1.1" over |
| Korean Air | Too tall (11" > 7.5") | Too tall (10.5" > 9.8" soft max) |
| LATAM Airlines | Too big | Too big |
| LOT Polish Airlines | Too tall (11" > 7.9") | Flexes — 2.6" over |
| Lufthansa | Too tall (11" > 9.1") | Flexes — 1.4" over |
| Norwegian | Too big | Too big |
| Pegasus Airlines | Fits | Fits |
| Porter Airlines | Too tall (11" > 10.5") | Exact fit |
| Royal Air Maroc | Soft-sided not accepted | Soft-sided not accepted |
| SAS Scandinavian Airlines | Too big | Too big |
| Saudia | Fits | Fits |
| Southwest Airlines | Too big | Too big |
| Sun Country Airlines | Too tall (11" > 9") | Flexes — 1.5" over |
| Swiss International Air Lines | Too tall (11" > 9.1") | Flexes — 1.4" over |
| TAP Air Portugal | Too tall (11" > 9") | Flexes — 1.5" over |
| Transavia | Too big | Too big |
| Turkish Airlines | Too big | Too big |
| United Airlines | Exact fit | Exact fit |
| Viva Aerobus | Too tall (11" > 8.3") | Flexes — 2.2" over |
| Volaris | Too tall (11" > 7.5") | Flexes — 3" over |
| Vueling | Too tall (11" > 8.3") | Flexes — 2.2" over |
| WestJet | Too big | Too big |
19 airlines where size doesn't decide it (no pets in the cabin, or no published size)
| Aer Lingus | No cabin pets | No cabin pets |
| Aeroméxico | Size not published | Size not published |
| Air New Zealand | No cabin pets | No cabin pets |
| ANA (All Nippon Airways) | No cabin pets | No cabin pets |
| British Airways | No cabin pets | No cabin pets |
| Cathay Pacific | No cabin pets | No cabin pets |
| China Airlines | No cabin pets | No cabin pets |
| Croatia Airlines | Size not published | Size not published |
| easyJet | No cabin pets | No cabin pets |
| Emirates | No cabin pets | No cabin pets |
| Icelandair | No cabin pets | No cabin pets |
| Japan Airlines | No cabin pets | No cabin pets |
| Mokulele Airlines | Size not published | Size not published |
| Qantas | No cabin pets | No cabin pets |
| Qatar Airways | No cabin pets | No cabin pets |
| Ryanair | No cabin pets | No cabin pets |
| Singapore Airlines | No cabin pets | No cabin pets |
| Southern Airways Express | Size not published | Size not published |
| Virgin Atlantic | No cabin pets | No cabin pets |
Which should you buy?
The Sherpa Original Deluxe (Medium) — it is within the published limit of 11 of the 58 airlines with a published cabin limit, against 10 for the Petsfit (Medium) Expandable Soft-Sided. That is the whole verdict on airline fit; real under-seat space still varies by aircraft and seat.
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Choose the Sherpa Original Deluxe (Medium) if…
- Spring-wire top flexes down to squeeze under lower seats. Guaranteed On Board®.
- It clears 11 of 58 airlines with a published cabin limit outright — more than the Petsfit (Medium) Expandable Soft-Sided.
- Your pet is under ~16 lb.
Choose the Petsfit (Medium) Expandable Soft-Sided if…
- Zips to a compliant 17×11×11 for boarding, expands for extra room at the gate. Budget-friendly.
- It clears 10 of 58 airlines with a published cabin limit outright.
- Your pet is under ~13 lb.
Full profiles: Petsfit (Medium) Expandable Soft-Sided · Sherpa Original Deluxe (Medium) · best carriers ranked · all carriers
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Common questions
Which fits more airlines, the Petsfit (Medium) Expandable Soft-Sided or the Sherpa Original Deluxe (Medium)?
The Sherpa Original Deluxe (Medium) — it's within the published limit of 11 of the 58 airlines with a published cabin limit, against 10 for the other. Real under-seat space still varies by aircraft.
What's the size difference?
Petsfit (Medium) Expandable Soft-Sided: 17 × 11 × 11 in (up to ~13 lb). Sherpa Original Deluxe (Medium): 17 × 11 × 10.5 in (up to ~16 lb). Height is the strict dimension under a seat, and the Sherpa Original Deluxe (Medium) is the shorter of the two.
Are these figures measured or published?
Published — both sets of dimensions come from the manufacturers' product pages (linked on each carrier's profile), matched against each airline's official carrier limit. We don't invent measurements.