Airline Carry-On Size Chart: Personal Item and Cabin Bag Rules by Airline

Carry-on rules are easiest to misunderstand when you are rushing to pack, and they are most expensive when you get them wrong at the gate. Airline cabin bag allowances vary by carrier, fare class, and sometimes route, so the same suitcase can be perfectly fine on one itinerary and too large or not included on the next. Use this chart as a quick-reference page before you book, pack, or swap airlines.

Quick-reference carry-on comparison chart

The table below is designed as an update-friendly snapshot of the airlines covered in the source evidence. It shows the standard carry-on size, personal item size, whether a free carry-on is included, and the fare or boarding notes travelers are most likely to care about.

What changed: Spirit’s baggage rules are included here only as a reference point from the source evidence. The source states that Spirit has ceased operations, so travelers should not use this as a current booking guide. United remains a current benchmark for a major U.S. airline.

How carry-on rules are measured

• Airline size limits usually include wheels, handles, and other attached parts, so measure the full outside of the bag.
• The familiar 22 x 14 x 9-inch carry-on benchmark is common on many U.S. airlines, but it is not a universal rule.
• A carry-on is the larger bag that typically goes in the overhead bin; a personal item is the smaller bag that must fit under the seat in front of you.
• Overhead space is not guaranteed, even if your bag fits the published dimensions.
• Leave a packing buffer below the limit so the bag still works when it is fuller on the return trip.

Major U.S. airline carry-on rules

United Airlines

United’s published carry-on size is 22 x 14 x 9 inches, and its personal item size is 17 x 10 x 9 inches. On most fares, travelers can bring one carry-on plus one personal item. The main exception in the source evidence is Basic Economy, which usually allows only a personal item.

United does not list an official carry-on weight limit in the evidence pack, but the bag still has to be light enough for you to place it in the overhead bin. The source evidence also notes that bags may be checked in a sizer at the gate, especially on full flights, which is why a bag close to the limit can become a problem even when it seems reasonable at home.

Spirit Airlines

The source evidence describes Spirit as a strict low-cost example with one free personal item and a paid carry-on policy. It lists the carry-on size at 22 x 18 x 10 inches and the personal item at 18 x 14 x 8 inches, with dimensions that include wheels and handles.

Because the source evidence says Spirit has ceased operations and that these baggage details are now reference-only, this section is best used to understand how budget-carrier baggage rules can differ from the more familiar major-airline benchmark. It should not be treated as a live booking policy.

Personal item rules: what usually fits and what does not

• Common personal items include purses, laptop bags, and small backpacks.
• The key test is whether the item fits fully under the seat in front of you.
• A bag marketed as “carry-on size” may still be too large to count as a personal item.
• Generic luggage labels are less useful than the airline’s actual dimensions, especially when the personal item limit is much smaller than the overhead-bag limit.

Budget airline traps to watch for

Budget carriers and low-fare ticket types are where travelers most often run into surprises. Even when a personal item is included, the larger carry-on may require payment or may not be included on the lowest fare. Basic Economy-style tickets can also remove overhead-bin eligibility on some airlines, which means the published carry-on rules matter as much as the fare rules.

Because baggage policies can shift, the safest habit is to verify the allowance before booking and then check it again before departure. If you are changing airlines or connecting to a different carrier, do not assume the same bag rules will apply on both segments.

How to avoid gate-check surprises

1. Measure the bag externally before you leave home, including wheels, handles, and any exterior pockets that affect size.
2. Check the fare class carefully so you know whether a carry-on is actually included.
3. Confirm whether your boarding group gives you a better chance at overhead-bin space.
4. Pack with a little room below the stated maximum instead of filling the bag to the edge.
5. Recheck the airline policy whenever you switch routes, airlines, or ticket types.

When to revisit this chart

• Before buying a new suitcase or backpack.
• Before booking a low-fare ticket.
• Before a trip where you plan to fly with only a carry-on.
• Before an international departure or any airline change on your itinerary.
• Whenever an airline announces a baggage policy update.

Rule of thumb: treat the published size as a hard maximum, not a target. A small amount of packing margin can save you from a gate-side repack, a baggage fee, or a delay while boarding.

Carry-on policies change often enough that it is worth checking them more than once. For other trip planning issues that can affect your journey, you may also want to review the Airport Delay Tracker Guide or, if your flight is disrupted, the Flight Cancellation Compensation Guide by Region.