In-cabin pet carriers that fit Frontier Airlines
The carriers from our list that clear Frontier Airlines' official 18 × 14 × 11 in under-seat limit — sorted best-fit first, with the ones that squeeze in when collapsed flagged.
Short answer: 13 of the 15 carriers we track fit Frontier Airlines' 18 × 14 × 11 in limit: 6 with room to spare on every side, 5 with no room to spare on at least one side and 2 only when collapsed or squeezed a little. 2 are too big.
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| Carrier | Size | Fit | Buy |
|---|---|---|---|
Sherpa Original Deluxe (Small) up to ~8 lb · max pet 13″ long × 7.5″ tall 15 × 10 × 8.5 in is within 18 × 14 × 11 in — 3" spare on length, 4" on width, 2.5" on height. · collapsible/flex · full fit detail → | 15 × 10 × 8.5 in | Fits | See on Amazon → |
 Mr. Peanut's Gold Series Mini (Low-Profile) up to ~15 lb 17 × 11 × 9 in is within 18 × 14 × 11 in — 1" spare on length, 3" on width, 2" on height. · collapsible/flex · full fit detail → | 17 × 11 × 9 in | Fits | See on Amazon → |
Petmate Soft-Sided Kennel Cab (Medium) up to ~10 lb 17 × 10 × 10 in is within 18 × 14 × 11 in — 1" spare on length, 4" on width, 1" on height. · full fit detail → | 17 × 10 × 10 in | Fits | See on Amazon → |
Sherpa Original Deluxe (Medium) up to ~16 lb · max pet 16″ long × 9.5″ tall 17 × 11 × 10.5 in is within 18 × 14 × 11 in — 1" spare on length, 3" on width, 0.5" on height. Tightest margin is 0.5", so measure before you fly. · collapsible/flex · full fit detail → | 17 × 11 × 10.5 in | Fits | See on Amazon → |
Diggs Passenger pet size not published · Diggs discontinued this carrier — link goes to similar carriers 17 × 12 × 10.5 in is within 18 × 14 × 11 in — 1" spare on length, 2" on width, 0.5" on height. Tightest margin is 0.5", so measure before you fly. · full fit detail → | 17 × 12 × 10.5 in | Fits | Search Amazon → |
Sleepypod Atom up to ~12 lb 17 × 8.5 × 10.5 in is within 18 × 14 × 11 in — 1" spare on length, 5.5" on width, 0.5" on height. Tightest margin is 0.5", so measure before you fly. · full fit detail → | 17 × 8.5 × 10.5 in | Fits | See on Amazon → |
Mr. Peanut's Gold Series Standard (Expandable) up to ~20 lb 18 × 11 × 10 in is within 18 × 14 × 11 in — 0" spare on length, 3" on width, 1" on height. Tightest margin is 0", so measure before you fly. · collapsible/flex · full fit detail → | 18 × 11 × 10 in | Exact fit | See on Amazon → |
ibiyaya JetPaw Expandable Backpack up to ~17 lb 18 × 12 × 10.5 in is within 18 × 14 × 11 in — 0" spare on length, 2" on width, 0.5" on height. Tightest margin is 0", so measure before you fly. · full fit detail → | 18 × 12 × 10.5 in | Exact fit | See on Amazon → |
Petsfit (Medium) Expandable Soft-Sided up to ~13 lb 17 × 11 × 11 in is within 18 × 14 × 11 in — 1" spare on length, 3" on width, 0" on height. Tightest margin is 0", so measure before you fly. · full fit detail → | 17 × 11 × 11 in | Exact fit | See on Amazon → |
Bergan Comfort Carrier (Small) pet size not published 16 × 8 × 11 in is within 18 × 14 × 11 in — 2" spare on length, 6" on width, 0" on height. Tightest margin is 0", so measure before you fly. · full fit detail → | 16 × 8 × 11 in | Exact fit | See on Amazon → |
Frisco Premium Airline-Compliant Carrier up to ~22 lb 18 × 11 × 11 in is within 18 × 14 × 11 in — 0" spare on length, 3" on width, 0" on height. Tightest margin is 0", so measure before you fly. · full fit detail → | 18 × 11 × 11 in | Exact fit | Search Amazon → |
Sleepypod Air up to ~18 lb Collapses from 22" to ~16" long, which fits — height 10.5" is within 11". · collapsible/flex · full fit detail → | 22 × 10.5 × 10.5 in | Fits collapsed | See on Amazon → |
SturdiBag Pro (Large, Flexible Height) pet size not published 11.5" tall vs a 11" limit — 0.5" over, but the flexible-height top compresses down. Verify it squeezes under your actual seat. · collapsible/flex · full fit detail → | 18 × 11.5 × 11.5 in | Flexes — 0.5" over | See on Amazon → |
Also checked, too big for Frontier Airlines: Away The Pet Carrier · Sherpa Original Deluxe (Large) — each one shows the exact measurement it misses by.
Every fit is against the published maximum; real under-seat space varies by aircraft (why). Full rules & fees: Frontier Airlines pet policy → · how Frontier Airlines ranks on fee and space →
Other airlines: GOL Linhas Aéreas · Hawaiian Airlines · Iberia · ITA Airways · JetBlue · JSX
Common questions
What size pet carrier does Frontier Airlines allow in the cabin?
Frontier Airlines' published limit for a carrier under the seat in front of you is 18 × 14 × 11 in. Weight limit: not published. We last checked this against Frontier Airlines' own pet policy on 2026-09-04.
How many pet carriers fit Frontier Airlines' limit?
13 of the 15 carriers we track fit Frontier Airlines' 18 × 14 × 11 in limit: 6 with room to spare on every side, 5 with no room to spare on at least one side and 2 only when collapsed or squeezed a little. 2 are too big.
Which carriers only fit Frontier Airlines when collapsed or squeezed?
Sleepypod Air, SturdiBag Pro (Large, Flexible Height). Each is over the published size until folded or pressed down, so measure yours and expect it may be checked at the gate.
Which carriers are too big for Frontier Airlines?
Away The Pet Carrier, Sherpa Original Deluxe (Large). Each is over the 18 × 14 × 11 in limit.
How much does Frontier Airlines charge for a pet in the cabin?
$149 per pet, each way (non-refundable). Confirm the current fee with Frontier Airlines when you book.