Carry-On Bag Size by Airline: The 2026 Dimension Guide

• 22x14x9 in

  Delta and JetBlue carry-on reference, wheels and handles included

• 45 in

  Delta's combined length-plus-width-plus-height ceiling

• 10x16x24 in

  Southwest's stated free carry-on external dimensions

• 17x13x8 in

  JetBlue's published personal-item limit

“Standard carry-on size” is one of the most repeated phrases in travel advice, and one of the least reliable. There is no single federal carry-on dimension. TSA tells travelers to ask the airline, and each airline publishes its own number. The bag that flies free on one carrier can be checked for a fee at the gate on another.

This guide records only what is stated on each airline’s current official page and verifiable from that page. Where the dimension could not be confirmed from the live source, the guide does not invent one. Start with the airline you booked, then use this page to understand how the numbers work and where the common failure points are.

Who decides what fits and what flies

The practical result is a two-step check before every trip. First, confirm the size your airline names on its current carry-on page. Second, confirm the content rules on TSA’s “What can I bring” list for the items you actually carry. Neither step is a substitute for the other, and neither can be answered by a generic “it fits” claim.

The check-in, online and gate systems may all state a different dimension than the marketing page you read. When they disagree, the published carry-on page and the physical sizer at the airport are the evidence that matters. Capture the number in a screenshot before you leave, so you have the current source if staff are working from older guidance.

Current carry-on limits across major U.S. carriers

Read the table right to left. The allowed count tells you how many bags; the dimension tells you the size; the personal-item rule tells you whether the second bag has its own limit. For American, United and Alaska, the current page is the source this guide defers to because a number could not be confirmed from the live page during this review.

Delta: 22 by 14 by 9 and the linear-inch test

Delta’s carry-on page says each passenger can bring one carry-on and one personal item free, and sets two tests for the larger bag: no single dimension over 22" x 14" x 9" (56 x 35 x 23 cm), and a combined length, width and height of no more than 45 linear inches (114 cm). The page says wheels and handles are included.

The linear-inch number is easy to miss but important. A bag that is 22" long, 14" wide and 9" tall is exactly 45 linear inches. If a bag is slightly deeper or wider, the sum can exceed 45 even when no single number looks large. Measure the packed bag in that order and compare the total, not just the largest side.

Delta also notes that on connection and small-aircraft flights, such as Delta Connection with 50 seats or fewer, only a personal item may be permitted because of limited overhead space, and larger items can be gate checked. The airline — not a national size — decides the limit for those aircraft, so check the equipment when you book.

JetBlue: size and the personal-item limit

JetBlue’s carry-on help page says every customer can bring one carry-on and one personal item on all fares. Its stated carry-on limit is 22" L x 14" W x 9" H, and the page explicitly includes wheels and handles in that measure. JetBlue also states there is no current carry-on weight limit, only that you be able to lift the bag.

The personal item gets an exact number on JetBlue’s page: 17" L x 13" W x 8" H. That is useful because many carriers describe the under-seat fit without publishing inches. If you travel JetBlue on a trip where the same bag also needs to satisfy another airline, use the stricter of the two personal-item rules for the connecting flight.

The no-weight-limit note matters in comparison because weight varies widely by carrier and route. JetBlue’s explicit statement is current as of this review; do not carry that assumption to another airline that has not published the same rule. Review the checked-bag fee comparison when a bag would not fit and you want the cost before you decide.

Southwest: free carry-on at 10 by 16 by 24

Southwest’s optional-travel-charges page says every ticketed passenger can carry on a carry-on bag and a smaller personal item for free, and it names the carry-on size: a bag that does not exceed the external dimensions of 10 x 16 x 24 inches. The personal item must fit under a seat or in the overhead compartment.

Southwest’s number is smaller than the 22-inch reference in one dimension and larger in another, which is exactly the point of this guide: the numbers are airline-specific. A standard 22" roller that fits Delta or JetBlue may exceed Southwest’s stated 24-inch external dimension once wheels and handles are added. Measure against the specific number, not the familiar one.

Southwest changed its checked-bag fees in 2026, but the carry-on remains free for ticketed passengers on its current page. That separation is worth noting: a free carry-on and a paid checked bag are different products, and a traveler who brings a bag that does not fit still faces whatever the gate policy is at the time.

American, United and Alaska: check the carrier

American, United and Alaska each operate a current carry-on page, but this guide does not restate a dimension it could not confirm from the live source during this review. That is the conservative choice: an airline carry-on number changes when the airline changes it, and an out-of-date table is worse than none. Use the airline’s own page as the final word.

The same logic applies when a ticket involves more than one airline, as it does on codeshare and partner itineraries. Codeshare flights can be sold by one airline and flown by another, and the operating airline’s aircraft and staff often set the practical size. Check every carrier on the itinerary before you commit to one bag.

When a site gives a generic “standard” dimension, compare it against the airline’s page rather than trusting the search result. A fare or partner page can lag the current limit. A short search on the airline’s official site takes less time than a gate fee, and the official number is the one staff are trained to enforce.

Personal items: the under-seat question

The personal item is where basic economy most often changes the picture. On some basic fares, the free allowance is a personal item only, and a roller bag must be checked or purchased separately. The basic economy versus main cabin comparison covers when that trade-off is worth it; this page focuses on the sizing.

If a purse and a small backpack are both useful, check whether the airline counts them as one item or two. Most U.S. carriers allow one personal item per passenger, meaning a camera bag plus a backpack can already be two. Confirm the count and the size together, because both are enforced at the gate.

Wheels, handles and how sizers really measure

Where an airline says wheels and handles are included, the number is the maximum of the physical bag with those parts. Delta and JetBlue are explicit on this. The practical failure is a bag built to a marketing “cabin size” that is taller with the handle extended than the airline states. Test it handle extended and fully packed.

Sizers vary between airports and even between gates, so a bag that fits one sizer can be borderline at another. Leave a small margin rather than buying a bag that sits exactly at the limit. A bag near the ceiling in every dimension also leaves no room for the soft-sided bulge that comes from an overstuffed compartment.

A measured square bag is only part of the story. The fit overhead also depends on the aircraft and how full the bins are. Delta notes that on very full flights or small aircraft, staff may require gate checking even for a bag that fits. Size your bag to the limit and plan to gate check when the flight is clearly full.

When fare type or aircraft changes the allowance

Fare type and aircraft change the practical allowance even when the airline’s headline page does not. Basic economy can remove the carry-on, and regional or partner flights can restrict overhead bins. Read the fare’s baggage rule and the operating airline’s page, because the airline flying the plane is the one setting the size at boarding.

For a bag that will not fit under the rules of the fare, price the alternatives before you travel. A paid checked bag is a deliberate choice, not a surprise, when the numbers are known in advance. Compare the fees and choose which product the trip actually needs rather than carrying a bag and hoping it passes.

A pre-trip carry-on checklist

1. Name every airline. List each operating carrier on the itinerary, not just the first.
2. Open each airline's current carry-on page. Record the dimension, the personal-item rule and the allowed count.
3. Check the fare. Note whether basic economy or a partner flight changes the allowance.
4. Pack and measure the bag. Extend handles, fully pack, and confirm it stays under the strictest number.
5. Confirm contents with TSA. Verify liquids, batteries and any restricted items on the TSA list.
6. Recheck before you leave. Sizes are current as of 11 August 2026; verify the airline page again before departure.

The single rule that survives every airline change is to match the carrier you actually booked. TSA governs what flies, the airline governs what fits, and the moment you trust a generic dimension over the airline’s page is the moment a bag gets checked at the gate. Measure once, against the right number, and the trip starts with the bag already on board.