Carry-On Duffel Bag Size: What Fits on Each US Airline (2026)
Disclosure: Hnlsharing is reader-supported. When you buy through links on our site, we may earn an affiliate commission at no extra cost to you. This does not change our verdicts.
“Carry-on size” is not one number. Most big US airlines use 22 × 14 × 9 inches, but Southwest, Frontier, Spirit, Allegiant and Sun Country each set their own limits, and budget fares often do not include a carry-on at all. We read each airline’s baggage page on October 3, 2026 and checked how common duffel bags measure up.
The short answer
A carry-on duffel bag can be up to 22 × 14 × 9 inches (about 56 × 36 × 23 cm) on American, Delta, United, JetBlue, Alaska and Avelo, including handles and straps. Southwest and Frontier allow 24 × 16 × 10 inches, Sun Country 24 × 16 × 11, Spirit 22 × 18 × 10 and Allegiant 22 × 16 × 10. A 22 × 14 × 9-inch box holds about 45 liters, so a 35- to 40-liter duffel is the practical maximum. For bags that fit, see our best carry-on duffel bags.
Carry-on and personal item limits by US airline
| Airline | Carry-on limit (in) | Personal item limit (in) | Lowest fare includes a carry-on? |
|---|---|---|---|
| American | 22 × 14 × 9 | 18 × 14 × 8 | Yes (Basic Economy boards last; bins may be full) |
| Delta | 22 × 14 × 9, max 45 linear in | No size published | Yes (except small Delta Connection flights) |
| United | 22 × 14 × 9 | 17 × 10 × 9 | No — Basic Economy: personal item only on most routes |
| Southwest | 24 × 16 × 10 | No size on its current help page | Yes |
| Alaska | 22 × 14 × 9 (45 in total) | No size published | Yes (Saver) |
| JetBlue | 22 × 14 × 9 | 17 × 13 × 8 | Yes (all fares) |
| Spirit | 22 × 18 × 10 | 18 × 14 × 8 | No — Value fare: buy a carry-on |
| Frontier | 24 × 16 × 10, up to 35 lb | 18 × 14 × 8 | No — personal item only |
| Allegiant | 22 × 16 × 10 | 18 × 14 × 8 | No — carry-on fee $10–$75 |
| Sun Country | 24 × 16 × 11, up to 35 lb | 17 × 13 × 9 | No — personal item only |
| Avelo | 22 × 14 × 9 | 17 × 13 × 9 | No — carry-on fee $52–$75 |
Limits are from each airline’s own baggage pages, read on October 3, 2026. Delta, Southwest and Alaska do not publish personal-item dimensions; they ask that the item fit under the seat in front of you. On Delta Connection flights with 50 seats or fewer, only personal items are allowed on board.
Need a carry-on duffel that fits the 22 × 14 × 9 box? The JenniBag Travel Bag 2.0 is listed at 21 × 9 × 12 inches, from $98 — offers checked 3 Oct 2026.
How popular duffels measure up
| Duffel (listed size) | 22 × 14 × 9 | 22 × 18 × 10 (Spirit) | 24 × 16 × 10 (Southwest, Frontier) |
|---|---|---|---|
| Nomatic Travel Duffel 40L (21 × 14 × 9 in) | Fits | Fits | Fits |
| JenniBag Travel Bag 2.0 (21 × 9 × 12 in) | Fits | Fits | Fits |
| Patagonia Black Hole Duffel 40L (19.7 × 12.5 × 8.5 in) | Fits | Fits | Fits |
| Away Featherlight Weekender (20.9 × 9.4 × 13.8 in) | Close (9.4 in deep) | Fits | Fits |
| Calpak Luka Large Duffel (19 × 14.25 × 9.5 in) | Close | Fits | Fits |
| Béis The Weekender (17.91 × 15.75 × 9.84 in) | No (15.75 in) | Fits | Fits |
| Halfday Garment Duffel 45L (22 × 12 × 12 in) | No (12 in deep) | No | No |
We compared each bag’s listed dimensions in any orientation. Soft bags compress, so a “close” result usually passes when the bag is not overstuffed; a clear “no” means the bag is larger than the limit even before you pack it.
A worked example: 21 × 9 × 12 inches
Take a duffel listed at 21 × 9 × 12 inches, like the JenniBag Travel Bag 2.0. Laid flat, its length (21) is under 22, its width (12) is under 14 and its depth (9) equals the 9-inch limit, so it fits the standard box on paper. The catch is the last inch: a soft duffel packed to the zipper bulges past 9 inches, and some reviewers of this bag say it is hard to close when full. Leave a little slack, or move shoes to your personal item, and it will slide into the sizer. Our JenniBag carry-on size check goes airline by airline.
How to measure a duffel bag
- Pack it first. Measure the bag as you will fly with it, not empty.
- Measure the longest, widest and deepest points, including outside pockets, handles, feet and any wheels.
- Try both orientations. A duffel can go into the sizer on its side; what matters is that each side fits within the matching limit.
- Weigh it on budget airlines. Frontier and Sun Country cap carry-ons at 35 pounds.
Tip: If your fare does not include a carry-on — United Basic Economy, Spirit Value, Frontier or Sun Country base fares — a duffel small enough for the personal-item limit is the only free option. Check that limit, not the carry-on one.
Carry-on duffel, personal item or checked bag?
- Personal item (about 20–25 liters): must fit under the seat; United’s 9 × 10 × 17 inches is the strictest limit among major airlines.
- Carry-on duffel (35–45 liters): goes in the overhead bin; check that your fare includes it.
- Checked duffel: anything larger, including most 55-liter and bigger duffels, and garment bags that do not fit the carry-on box.
If you would rather roll than carry, our guide to carry-on duffels with wheels checks each wheeled model against the same 22 × 14 × 9-inch box.
Want a duffel that also hangs a suit or dress? JenniBag Travel Bag 2.0, plus our code listed at 15% off — offers tracked on our JenniBag coupons page, checked 3 Oct 2026.
Frequently Asked Questions
What is the maximum carry-on duffel bag size?
On American, Delta, United, JetBlue, Alaska and Avelo, a carry-on can be up to 22 × 14 × 9 inches, including handles and wheels. Southwest and Frontier allow 24 × 16 × 10 inches, Sun Country 24 × 16 × 11, Spirit 22 × 18 × 10 and Allegiant 22 × 16 × 10.
Does a duffel bag count as a carry-on or a personal item?
It depends on its size. A full-size duffel of 35 to 45 liters is a carry-on and goes in the overhead bin. Only a small duffel that fits under the seat — for example within United’s 9 × 10 × 17 inches or American’s 18 × 14 × 8 inches — counts as a personal item.
How many liters is a carry-on duffel?
A 22 × 14 × 9-inch box holds about 45 liters, so most carry-on duffels are 35 to 40 liters. Bags advertised at 50 or 60 liters rely on soft sides squeezing into the sizer and may not fit when fully packed.
Do airlines measure soft duffel bags?
They can. Gate agents may ask you to place any carry-on in the sizer, and a soft duffel that bulges when full can fail even if its listed size fits. Spirit says personal items must fit in its smaller sizer bin, and Frontier says it checks personal-item size during boarding.
Is a 24-inch duffel bag carry-on size?
Only on airlines with a 24-inch limit: Southwest and Frontier (24 × 16 × 10 inches) and Sun Country (24 × 16 × 11). On American, Delta, United, JetBlue and Alaska the longest side can be only 22 inches.
Do carry-on size limits include handles and straps?
Yes. American, Delta, United and JetBlue include handles and wheels, Frontier includes straps, and Allegiant includes pockets, handles and decorations. Measure the bag at its widest points, including any outside pockets.
Read next
- Best Carry-On Duffel Bags of 2026
- Best Carry-On Duffel Bags With Wheels (2026)
- Does JenniBag Fit as a Carry-On? An Airline-by-Airline Size Check
- Best Garment Duffel Bags of 2026: 2-in-1 Carry-Ons Compared
- Best Carry-On Bags of 2026: Duffels, Garment Bags and Backpacks
- JenniBag Guide: every review, sizing guide and deal in one place
The bottom line
Plan around 22 × 14 × 9 inches and about 40 liters, and your duffel will fit almost every US airline’s carry-on limit. If you fly Southwest or Frontier you have a little more room, and if your fare only includes a personal item, the size that matters is the one under the seat.
