Is an underseat bag the same as a carry-on bag?

Similar to carry-on luggage, underseat luggage is subject to size and shape requirements. However, unlike most of the things people fly with—nearly all of which are precisely designed for airplane use—almost any small bag (your favorite backpack or tote, for instance) can work as a personal item.



In 2026 airline terminology, an underseat bag (often called a "Personal Item") is distinctly different from a standard "Carry-on" (or "Cabin Bag"). A personal item must be small enough to fit completely beneath the seat in front of you—standard dimensions are typically around 18 x 14 x 8 inches. This category includes items like small backpacks, purses, or laptop bags. Conversely, a standard carry-on bag is larger (typically up to 22 x 14 x 9 inches) and is designed to be stored in the overhead bin. The distinction is critical for budget-conscious travelers: many "Basic Economy" or "Ultra-Low-Cost" fares (like those on Frontier, Spirit, or Ryanair) include one personal item for free but charge a significant fee for a standard carry-on. If you arrive at the gate with an "underseat bag" that exceeds the sizing sizer, the airline may force you to gate-check it for a fee of $65 or more. While both travel in the cabin with you, the underseat bag is your "essential access" gear, while the carry-on is your primary storage for clothing and bulkier items that you don't need to reach during the actual flight.

People Also Ask

The size restrictions for underseat luggage vary greatly between different airlines. It can range anywhere from 13 x 10 x 8 inches to 18 x 14 x 10 inches. But in general, if your underseat luggage is under 16 x 12 x 6 inches, it should be allowed on most airlines.

MORE DETAILS

Domestic carry-on policies. A good rule of thumb is that if your carry-on bag fits under the seat in front of you, it's considered a personal item. This includes small backpacks, purses, briefcases, laptop bags, etc. Larger bags, including suitcases, must fit in the overhead bin compartment.

MORE DETAILS

Usually, many airlines won't check every carry-on but will instead go for ones that look oversized. If your luggage does not fit in the sizer, you might have to pay a checked bag fee along with the gate checking fee and have your bag transferred to the airplane's cargo.

MORE DETAILS

Firearms, ammunition, and fireworks are prohibited, as are all knives and safety razors (including pocket knives and Swiss Army knives). Straight razors and replacement blades for straight razors are also not allowed. Most tools also cannot be packed in carry-on luggage, as they have the potential to cause harm.

MORE DETAILS

A personal item is any small bag that fits beneath the seat in front of you. Possible personal items include purses, laptop bags, camera bags, totes, diaper bags, and small backpacks.

MORE DETAILS

American Airlines
According to airline policy, any personal items stowed beneath seats should not exceed 18 inches by 14 inches by 8 inches.

MORE DETAILS

Most airlines allow passengers to bring on both a carry-on and a personal item like a backpack, laptop bag, purse, briefcase, shopping bag, etc. The general rule of thumb is that your personal item is smaller in dimension than your carry-on bag and it can fit underneath the seat in front of you.

MORE DETAILS

If your carry-on is too big, you will either have to pay penalty fees or check your luggage. Checking your luggage means that your carry-on won't be traveling with you but will instead be sent to the airplane cargo, and you will be able to claim it once the plane lands.

MORE DETAILS

? Flight Approved Carry on Backpack: Size of travel backpack: 20.47 x 12.99 x 8.66 . Capacity: 35L. This luggage backpack is meet the allowed maximum size of most IATA flights and also fits in the overhead compartment and the underseat in flight.

MORE DETAILS

Many airlines do not actually put a size limit on your personal item, only that it must fit underneath the seat in front of you. In fact, even the airlines that do have size limits say the same thing, your personal item always has to fit under the seat in front of you.

MORE DETAILS

Carry-on bags are limited to 22 inches long, 14 inches wide and 9 inches high including wheels and handles. All three measurements shouldn't add up to more than 45 inches.

MORE DETAILS

Delta underseat dimensions are 20 inches X 15 inches X 11 inches (55 cm X 38 cm X 28 cm) on most aircraft. To ensure your personal item fits these dimensions, choose an item that is 17 inches X 13 inches X 9 inches (43 cm X 33 cm X 23 cm) or smaller.

MORE DETAILS

As a general rule of thumb, anything smaller than the dimensions of a carry-on can be considered a personal item. However, every airline has different restrictions for size. In most cases, your backpack should be no more than 18 x 14 x 8 inches.

MORE DETAILS

A personal item is any type of luggage that fits underneath the plane seat in front of you. Most domestic airlines in the United States require a personal item to be 18” x 14” x 8” or smaller in size. Personal items can include a purse, briefcase, small backpack, laptop bag, weekender or small duffel bag.

MORE DETAILS

No stone unturned! Flight attendants sure know what they're doing, but so do savvy shoppers: more than 3,000 of them have give this weekender five-star ratings. “Cute, functional — and yes, it fits under every airline seat,” wrote one helpful shopper.

MORE DETAILS

As long as you keep your liquid or aerosol deodorant in a container that is smaller than 3.4 ounces (100ml) and store it in a quart-sized, zip-top bag, you shouldn't have a problem traveling with it. There are no restrictions for packing solid deodorants in your carry-on luggage.

MORE DETAILS

Is toothpaste considered a liquid by the TSA? Yes, toothpaste must adhere to the 3-1-1 rule for liquids and gels. Toothpaste can be brought through TSA security in your carry-on as long as it is 3.4 ounces (100 milliliters) or less and placed in a 1-quart bag.

MORE DETAILS

As long as the backpack meets the personal item requirements for size, you can put anything in, even your purse. Yes.

MORE DETAILS

In general, standard domestic carry-on luggage size is 22 x 14 x 9 inches. If you're flying internationally, that may vary a little to 21.5 x 15.5 x 9 inches. Remember, those dimensions include the handle, wheels and anything else that may protrude from your suitcase so don't miss them from your measurements.

MORE DETAILS

While these sizes vary by airline, a personal item will typically measure no more than 18 x 14 x 8 inches or 45 x 35 x 29 cm. If your bag does not fit within these dimensions, the airline will likely consider it your 'carry-on' bag and charge you accordingly.

MORE DETAILS