The under-seat personal item is free on every US airline without exception. The overhead bin is not. Four carriers charge for it outright and one strips it from the cheapest fare class — and on the carriers that charge, the price roughly triples between booking and the gate.
| # | Airline | Carry-on | Cost | What it runs |
|---|---|---|---|---|
| 1 | Allegiant Air | 22 × 16 × 10 | Paid | $10–75 depending on route and when you buy |
| 2 | Breeze Airways | 22 × 14 × 9 | Paid | $35–37 online around $50 at the airport up to $75 late |
| 3 | Frontier Airlines | 24 × 16 × 10 | Paid | $29–69 at booking $39–86 after $79–92 at the airport $99–115 at the gate |
| 4 | Sun Country Airlines | 24 × 16 × 11 | Paid | $25–40 at booking around $50 after $55 plus a $10 gate fee at the airport |
| 5 | United Airlines | 22 × 14 × 9 | Depends on fare | Not included on Basic Economy for most routes. |
| 6 | Alaska Airlines | 22 × 14 × 9 | Free | Free on every fare — Saver fares still include a full carry-on. |
| 7 | American Airlines | 22 × 14 × 9 | Free | Free on every fare — Basic Economy gets a full carry-on plus a personal item. |
| 8 | Delta Air Lines | 22 × 14 × 9 | Free | Free on every fare — Delta does not strip the carry-on from Basic Economy. |
| 9 | Hawaiian Airlines | 22 × 14 × 9 | Free | Free on every fare. |
| 10 | JetBlue | 22 × 14 × 9 | Free | Free on every fare — Blue Basic has included a carry-on since September 2024. |
| 11 | Southwest Airlines | 24 × 16 × 10 | Free | Free on every fare, including the cheapest Basic fare. |
Prices are the carriers’ published ranges and move with route and demand — treat them as the shape of the pricing rather than a quote. The pattern worth remembering is that every one of these airlines prices the bag lowest at booking and highest at the gate, so the cheapest headline fare is rarely the cheapest trip once a carry-on is added. Verified August 2026.
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Frontier Airlines, Allegiant Air, Breeze Airways, Sun Country Airlines charge for the overhead bin. United Airlines includes it on most fares but not Basic Economy. The under-seat personal item is free on every US airline.
Yes, without exception. Every US carrier includes one free under-seat personal item on every fare class, including Basic Economy and the cheapest ultra-low-cost fares. Only the overhead-bin carry-on ever costs extra.
Yes, on every US airline. They measure the outside of the bag, so wheels, handles, straps and external pockets all count. This is why a suitcase sold as a "20-inch carry-on" is often 22 inches overall.
Airlines revise baggage policy without announcement, usually alongside fare changes. Every figure here was checked against the carrier’s own published policy in August 2026 and each links to the source it came from.
Manufacturers publish dimensions inconsistently, and a “20-inch” spinner is almost never 20 inches once you count the wheels. Where a brand states dimensions including wheels and handles, that’s the number we use. Where it only publishes the case, we say so on the card. Airlines measure the outside of your bag — wheels, handles, straps and all. Anything marked borderline is down to the gate agent, and remember that a soft bag squashes into a sizer while a hard shell won’t.
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Limits verified August 2026 against each carrier’s published policy. Airlines change these without notice — always confirm before you fly. Spirit Airlines ceased operations on 2 May 2026 and is no longer listed.
Airline Bag Size Checker v1.0.15 · last updated 2026-08-12