Allegiant Air in-cabin pet policy — and the carriers that fit
Allegiant Air allows small pets in the cabin in a carrier up to 18 × 12 × 11 in, stowed under the seat in front of you. Already own a carrier? Enter its measurements below to check it against this limit. The in-cabin fee is $50 per segment, per carrier. 11 of the 15 carriers we track clear that published limit.
The Sherpa Original Deluxe (Small) leaves the most room — 2" on its tightest dimension, while the Mr. Peanut's Gold Series Standard (Expandable) only just squeaks in with nothing to spare. Allegiant's 11" height ceiling sits mid-pack among the 77 airlines we track (shared with American, American Eagle (regional, incl. Republic Airways), Copa, Delta, Frontier, JSX, United): Air Europa, Avelo, Breeze and Pegasus allow more, while EL AL Israel allows only 7".
Will your carrier fit Allegiant Air?
Measure the outside of your carrier (bulges included) and enter it below. The check uses Allegiant Air’s published 18 × 12 × 11 in limit — height is checked strictly, the footprint may rotate.
Carriers that clear Allegiant Air (18 × 12 × 11 in)
Roomiest margin first. Sized to the airline’s limit, not to your pet — measure your pet first →
| Carrier | Size | Fit | Buy |
|---|---|---|---|
Sherpa Original Deluxe (Small) up to ~8 lb · max pet 13″ long × 7.5″ tall | 15 × 10 × 8.5 in | Fits 2" spare | See on Amazon → |
 Mr. Peanut's Gold Series Mini (Low-Profile) up to ~15 lb | 17 × 11 × 9 in | Fits 1" spare | See on Amazon → |
Petmate Soft-Sided Kennel Cab (Medium) up to ~10 lb | 17 × 10 × 10 in | Fits 1" spare | See on Amazon → |
Affiliate link — we may earn a small commission at no extra cost to you. It never changes our specs or which carriers we list.
Allegiant Air pet rules
| Max soft-sided carrier | 18 × 12 × 11 in |
| Max hard-sided kennel | 17 × 11 × 10.5 in |
| Soft-sided required? | Soft recommended; hard allowed within its limit |
| In-cabin fee | $50 per segment, per carrier · compare all airlines → |
| Species allowed | dogs, cats |
| Minimum age | At least 8 weeks |
| Pets | 1 carrier per traveler (up to 2 pets per carrier); counts as 1 of your 2 carry-on items |
| Booking | Check in with an Allegiant agent at the ticket or gate counter at least 1 hour before departure. Cabin pets allowed within the 48 contiguous US only. · what to book, buy and pack → |
| Seating restrictions | Not in the exit row or bulkhead; on Boeing aircraft pet carriers are not allowed in aisle seats (Allegiant moves you if you picked one). |
| Routes & cargo | Allegiant does not carry animals in the cargo hold. Cabin pets are welcome within the 48 contiguous states; Allegiant says flights to international destinations and U.S. territories do not accept all pets, so check with Allegiant before booking a trip outside the lower 48. |
Source: official Allegiant Air pet policy · verified 2026-09-24 · how Allegiant Air ranks on fee and space →
Carriers that fit Allegiant Air
Matched to Allegiant Air's published 18 × 12 × 11 in limit (height checked strictly; footprint may rotate). See the full Allegiant Air carrier shortlist →
Affiliate link — we may earn a small commission at no extra cost to you. It never changes our specs or which carriers we list.
This table ranks by Allegiant Air’s size limit — not by your pet. The weight under each carrier is what that size is rated to hold. A bag can clear the airline and still be the wrong size for the animal, which is the most common reason one goes back — measure your pet first →
| Carrier | Size | Fit | Buy |
|---|---|---|---|
Sherpa Original Deluxe (Small) up to ~8 lb · max pet 13″ long × 7.5″ tall | 15 × 10 × 8.5 in | Fits 2" spare | See on Amazon → |
Mr. Peanut's Gold Series Mini (Low-Profile) up to ~15 lb | 17 × 11 × 9 in | Fits 1" spare | See on Amazon → |
Petmate Soft-Sided Kennel Cab (Medium) up to ~10 lb | 17 × 10 × 10 in | Fits 1" spare | See on Amazon → |
Sherpa Original Deluxe (Medium) up to ~16 lb · max pet 16″ long × 9.5″ tall | 17 × 11 × 10.5 in | Fits 0.5" spare | See on Amazon → |
Sleepypod Atom up to ~12 lb | 17 × 8.5 × 10.5 in | Fits 0.5" spare | See on Amazon → |
Mr. Peanut's Gold Series Standard (Expandable) up to ~20 lb | 18 × 11 × 10 in | Exact fit 0" spare | See on Amazon → |
Diggs Passenger pet size not published · Diggs discontinued this carrier — link goes to similar carriers | 17 × 12 × 10.5 in | Exact fit 0" spare | Search Amazon → |
ibiyaya JetPaw Expandable Backpack up to ~17 lb | 18 × 12 × 10.5 in | Exact fit 0" spare | See on Amazon → |
Petsfit (Medium) Expandable Soft-Sided up to ~13 lb | 17 × 11 × 11 in | Exact fit 0" spare | See on Amazon → |
Bergan Comfort Carrier (Small) pet size not published | 16 × 8 × 11 in | Exact fit 0" spare | See on Amazon → |
Frisco Premium Airline-Compliant Carrier up to ~22 lb | 18 × 11 × 11 in | Exact fit 0" spare | Search Amazon → |
Sleepypod Air up to ~18 lb | 22 × 10.5 × 10.5 in | Fits collapsed | See on Amazon → |
SturdiBag Pro (Large, Flexible Height) pet size not published | 18 × 11.5 × 11.5 in | Flexes — 0.5" over | See on Amazon → |
2 carriers too big for Allegiant Air
Away The Pet Carrier pets up to ~18 lb | 18.7 × 10.8 × 10.75 in | Too big | Compare similar on Amazon → |
Sherpa Original Deluxe (Large) up to ~22 lb · max pet 18″ long × 10.5″ tall | 19 × 11.75 × 11.5 in | Too big | View on Amazon |
How to confirm your actual under-seat space
Allegiant Air's number is its published maximum, not a guarantee for your exact seat. Before you buy or fly:
- Check which aircraft operates your flight (in your booking or on a seat-map site).
- Avoid bulkhead and exit rows — bulkheads have no under-seat storage and most airlines ban pets there — and check this airline's seat rules above.
- Call Allegiant Air to confirm under-seat dimensions for that aircraft, or
- Choose a collapsible / flexible-height carrier that adapts to a tighter space.
More airlines: Air Canada · Alaska Airlines · American Airlines · Breeze Airways · Delta Air Lines · Frontier Airlines · Southwest Airlines · United Airlines · Asiana Airlines · all →
Common questions
What size pet carrier does Allegiant Air allow in the cabin?
Allegiant Air's recommended maximum in-cabin carrier is 18 × 12 × 11 in (soft) or 17 × 11 × 10.5 in for a hard-sided kennel. It must fit fully under the seat in front of you. Source: the Allegiant Air pet policy.
How much does Allegiant Air charge for an in-cabin pet?
$50 per segment, per carrier. Always confirm the current fee on the official Allegiant Air pet page before you fly.
Which pet carriers fit Allegiant Air?
11 of the 15 carriers we track clear Allegiant Air's published 18 × 12 × 11 in. The roomiest is the Sherpa Original Deluxe (Small), with 2" to spare on its tightest dimension. The heaviest pet any carrier that clears Allegiant Air is rated for is 22 lb (some fitting carriers publish no pet rating). Full shortlist: /fits/allegiant/.
Does Allegiant Air require a soft-sided pet carrier?
Allegiant Air recommends soft-sided but allows a hard-sided kennel within its published limit. Height is what rules carriers out: Allegiant Air publishes 11", against 13" at the most generous airline we track.
How many pets can I bring in the cabin on Allegiant Air?
1 carrier per traveler (up to 2 pets per carrier); counts as 1 of your 2 carry-on items. Species accepted: dogs, cats. Check in with an Allegiant agent at the ticket or gate counter at least 1 hour before departure. Cabin pets allowed within the 48 contiguous US only.