Most US airlines use a similar carry-on standard – but "similar" isn't "the same," and the differences matter at the gate. Basic economy fares, budget carriers, and personal item rules all add wrinkles that catch travellers off guard.
This guide is a 2026 reference for carry-on and personal item sizes on major US domestic airlines, plus the fare rules and gate-check realities worth knowing before flying.
For a carry-on sized to fit the common US standard: Carry-On Luggage.
Important: Airline policies change. Dimensions below reflect published limits at the time of writing – always confirm with the airline before flying, especially on regional aircraft or basic economy fares.
The US carry-on standard
The most common US carry-on limit is 22 × 14 × 9 inches (56 × 36 × 23 cm), measured including wheels and handles. American, Delta, United, JetBlue, Alaska, and Hawaiian all use this size or something very close to it.
Southwest, Frontier, and Sun Country allow slightly larger bags. Spirit and Allegiant have their own dimensions – and, along with Frontier, charge for a standard carry-on on most fares.
US carriers generally do not enforce carry-on weight limits – the bag simply needs to fit and be liftable into the overhead bin.
Carry-on and personal item sizes by airline (2026)
| Airline | Carry-on max (in) | Personal item max (in) | Notes |
|---|---|---|---|
| American Airlines | 22 × 14 × 9 | 18 × 14 × 8 | Carry-on included on all fares, including Basic Economy |
| Delta Air Lines | 22 × 14 × 9 | No set dimensions – must fit under the seat | Carry-on included on all fares; also references 45 linear inches |
| United Airlines | 22 × 14 × 9 | 17 × 10 × 9 | Basic Economy allows a personal item only on most domestic routes – full-size carry-on requires a fee or eligible status |
| Southwest Airlines | 24 × 16 × 10 | 16.25 × 13.5 × 8 | One of the most generous carry-on sizes in the US |
| JetBlue | 22 × 14 × 9 | 17 × 13 × 8 | Carry-on included on Blue fares and above; Blue Basic policies have varied – confirm before flying |
| Alaska Airlines | 22 × 14 × 9 | No set dimensions – must fit under the seat | Carry-on included on Saver fares |
| Hawaiian Airlines | 22 × 14 × 9 | No set dimensions – must fit under the seat | Carry-on included; personal item must fit under seat |
| Spirit Airlines | 22 × 18 × 10 | 18 × 14 × 8 | Personal item free; full carry-on is a paid add-on |
| Frontier Airlines | 24 × 16 × 10 | 14 × 18 × 8 | Personal item free; carry-on is a paid add-on on most fares |
| Allegiant Air | 22 × 16 × 10 | 16 × 15 × 7 | Personal item free; carry-on is a paid add-on |
| Sun Country Airlines | 24 × 16 × 11 | 17 × 13 × 9 | Carry-on is a paid add-on on most fares |
All dimensions include wheels and handles. Personal items must fit fully under the seat in front. Fare rules change frequently – verify with the airline before travelling.
Basic economy: what's actually included
Basic economy is where most carry-on surprises happen. The rules vary by carrier:
- American, Delta, Alaska, Hawaiian: a full-size carry-on is included on basic economy fares
- United: basic economy on most domestic routes includes only a personal item – a full carry-on costs extra unless the traveller has elite status or an eligible credit card
- JetBlue: Blue Basic carry-on rules have changed more than once – confirm at booking
- Spirit, Frontier, Allegiant, Sun Country: base fares include a personal item only; a carry-on is a paid add-on, and gate prices are higher than online prices
Cost tip: on budget carriers, adding a carry-on at booking is almost always cheaper than adding it at the airport.
Regional aircraft and gate-checking
A bag that meets the airline's published limit can still be gate-checked. Common reasons:
- Regional jets (CRJ and Embraer aircraft) have smaller overhead bins – bags are often "valet checked" planeside and returned at the jet bridge
- Full flights – later boarding groups may be asked to check bags when bins fill
- Overstuffed bags – an expanded or overpacked suitcase can fail the sizer even if the empty dimensions comply
Valet checking on regional jets is usually free and the bag comes back at the gate – but it still means a wait on arrival.
How to measure a carry-on for US airlines
- Height: ground to top of shell, including wheels
- Width: widest point, including side handles
- Depth: deepest point, including front pockets or expansion
- Handle: fully retracted
If the suitcase is expandable, measure it expanded and packed – that's the size the sizer will see. Browse: Expandables.
Choosing a carry-on that fits everywhere
A carry-on sized at or under 22 × 14 × 9 inches fits every major US carrier and most international airlines. Travellers who fly a mix of carriers – or fly internationally – benefit most from staying within that standard.
- Carry-On – fits the 22 × 14 × 9 standard: Shop carry-on
- Metro Bags – personal items that fit under the seat: Shop Metro
Related guides: Carry-on size limits by airline – global (2026) • International carry-on size guide • How to choose a carry-on
