Short answer
Bringing a pet in the cabin in 2026 typically costs $50 to $150 each way on major U.S. airlines. Budget carriers are often cheapest (Allegiant $50, Frontier $99), while the legacy carriers (United, Delta, American, JetBlue) sit at the top around $150 each way. The fee is charged per direction, so a round trip is roughly double.
The fee is only half the decision, though — you also have to be sure your carrier fits that airline’s published limit. A cheap fee on an airline your carrier does not fit is not a deal.
Why this matters
Pet fees are almost always non-refundable and the in-cabin pet slot is capacity-limited. Paying the fee and then being turned away for an oversized carrier is the worst outcome, so it is worth pricing the fee and checking the fit together.
In-cabin pet fees by airline
From each airline’s official pet policy, accessed 2026-07-10. Fees change frequently and some airlines set the amount by route at booking — always confirm on the airline’s own page.
| Airline | In-cabin pet fee | Published soft-sided carrier limit |
|---|---|---|
| Allegiant Air | $50 each way, per carrier per segment | 18 × 12 × 11 in |
| Frontier Airlines | $99 each way | 18 × 14 × 11 in |
| Alaska Airlines | $100 each way ($35 within Hawaii) | 17 × 11 × 9.5 in |
| Hawaiian Airlines | $100 each way per carrier | 17 × 11 × 9.5 in |
| United Airlines | $150 each way | 18 × 11 × 11 in |
| Delta Air Lines | $150 each way | 18 × 11 × 11 in |
| American Airlines | $150 per kennel each way | 18 × 11 × 11 in |
| JetBlue | $150 each way | 17 × 12.5 × 8.5 in |
A few notes worth knowing before you book:
- Southwest requires a Pet Fare but does not publish a simple in-cabin carrier dimension in the record we cite, so we mark its size rule unclear rather than guess. See the Southwest airline page.
- British Airways does not offer an in-cabin pet product on its own flights; pets travel in the hold via partners. It is marked no cabin pets.
- International carriers (Air France, KLM, Lufthansa) set the fee by route at booking, so there is no single number.
The fee is only half the answer
Frontier’s larger 18 × 14 × 11 in envelope and low $99 fee can be a great value — but only if you are actually flying Frontier. JetBlue’s 8.5 in height limit is the tightest on this list, so a tall carrier that clears United can still exceed JetBlue at a similar fee. This is why we always pair the fee with the fit.
A modest soft carrier such as the Sherpa Original Deluxe (Medium) or the low-profile Sleepypod Atom clears the common limits, but you should still confirm against your exact airline.
Recommended next step
Before you pay any pet fee, run your carrier through the fit checker for your airline, or compare every carrier and airline on the compare heat map. How we source and calibrate these results is on the methodology page.
Caveats
- Fees and rules change without notice; the amounts above reflect each airline’s official page as accessed 2026-07-10.
- A carrier that matches a published limit is not guaranteed to be accepted at the gate; under-seat space and gate discretion vary.
- We do not advise on your pet’s health, sedation, or fitness to fly — talk to your veterinarian and the airline.