How Much Underseat Space You Get on Every Major U.S. Airline

legroom under airplane seat flight room space
legroom under airplane seat flight room space

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Every time you board a plane, you probably hear flight attendants telling passengers to stow small, personal items under the seat in front of them and larger bags in the overhead bins. Of course, space on airplanes is notoriously tight these days, so you might be wondering just how much room you have under that seat in front of you. The answer? It depends. Many airlines don't list the exact underseat dimensions, but they do share the maximum size permitted for personal items, providing an approximate measure of how much space is under the average seat.

Any items that stick out could pose a safety hazard during an emergency evacuation, so flight attendants are usually pretty stringent on this rule. If fighting for overhead bin space doesn't appeal to you (and who does it appeal to?), knowing the measurements of the space under your seat could save you time and stress. This is even more important for pet owners traveling with their furry friends in the cabin. Thankfully, we've done the work for you and rounded up 10 of the best airline-approved pet carriers that will fit under the seat.

Related: Airline Carry-on Luggage Size Restrictions: What You Need to Know

It's important to remember that the exact airline underseat dimensions vary by aircraft — a Boeing 737 won't have the same seats as a Bombardier Q400 — and by individual seat, so these measurements are estimated, not exact. Roomy first-class seats may have a few extra inches to spare, and the main cabin middle seat might have more room than its neighbors. Meanwhile, people sitting at the bulkhead should remember that all that extra legroom does come at a price — these seats do not have underseat storage and passengers will have to put everything in the overhead bin.

Here are some of the most popular U.S. airlines' underseat dimensions and personal item sizes. And to make the most of the space, check out our picks for the best underseat luggage pieces that are still surprisingly roomy.

Related: More air travel tips

Alaska Airlines

The airline does not release exact measurements for the space below seats, instead using purses, briefcases, and laptop bags as examples of suitable personal items. The maximum size for carry-on luggage is 22 inches by 14 inches by 9 inches (including wheels and handles). The seat width is approximately 17 inches.

American Airlines

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

Delta Air Lines

Delta defines personal items that must fit under the seat as "a purse or laptop bag or item of similar size." Delta has a maximum carry-on size of 22 inches by 14 inches by 9 inches — no bag may exceed 45 linear inches combined.

Hawaiian Airlines

Hawaiian Airlines simply defines personal items as "a laptop bag, briefcase, purse, or backpack that can fit under the seat in front of you."

JetBlue

Under-the-seat baggage can not exceed 17 inches by 13 inches by 8 inches on all JetBlue flights. Note that travelers flying Blue Basic are only permitted a personal underseat item (not a carry-on bag).

United Airlines

The maximum size for a personal item that fits under the seat on United is 9 inches by 10 inches by 17 inches.

Southwest Airlines

Southwest doesn't provide exact underseat dimensions either, but they include "purses, briefcases, cameras, food containers, or laptops (case included)" as personal items that must be stored under the seat in front of you.

Spirit Airlines

Personal items must not exceed 18 inches by 14 inches by 8 inches, including handles and wheels, on Spirit Airlines.