Among US airlines, personal item limits run from 17 x 10 x 9 in on United to 18 x 14 x 8 in on American, Frontier and Allegiant. Delta, Southwest, Alaska and Hawaiian give no size. Delta and Southwest say it goes under the seat in front of you.
Neither airline gives a personal item size for Economy. Qatar Airways lets you bring a small purse or small briefcase besides the 7 kg carry-on, and Emirates’ cabin baggage page names no second item in Economy.
whatsizebag.com
A bag that fits every size here
Side by side, the smallest limit on each side is 17 x 10 x 8 inches, longest side first. A bag within that fits every US airline in the chart that gives a size. United’s limit is the one that sets the 10 inch side.
Frontier checks the personal item’s size at boarding and is the only US airline here with a weight limit for it, 35 pounds.
What counts as a personal item
The airlines name a purse, a briefcase, a laptop bag and a small backpack. Delta, American and United each list a few items you can bring on top of it, such as a jacket, an umbrella or a diaper bag. See personal item vs carry-on for how the two differ.
Common questions
Is a backpack a personal item?
Yes, Delta, Southwest, United and JetBlue list a backpack or small backpack as a personal item, as long as it fits the airline's under-seat limit.
Does Southwest have a personal item size?
No, Southwest's carry-on page gives no personal item size, only that it goes under the seat in front of you.
What size is the free under-seat bag in the UK and Europe?
UK and European airlines set these free under-seat bag limits, longest side first: Ryanair, Wizz Air, Jet2 and Aer Lingus 40 x 30 x 20 cm, easyJet 45 x 36 x 20 cm and British Airways, Lufthansa, KLM and Air France 40 x 30 x 15 cm.
Every personal item limit comes from the airline’s own baggage page, read in October 2026. Checked against published data from Frontier Airlines, Sun Country Airlines, Avelo Airlines, WestJet and American Airlines (plus 21 more).
See all 30 sources
American Airlines, Carry-on bags (aa.com)
Delta Air Lines, Carry-On Baggage (delta.com)
United Airlines, Carry-on bags (united.com)
Southwest Airlines, Carryon and Personal Item Policy (support.southwest.com)
WestJet, Baggage: checked baggage allowance and fees (westjet.com)
Porter Airlines, Carry-On Baggage (flyporter.com)
Ryanair Help Centre, Ryanair's Bag Policy (help.ryanair.com)
easyJet, Cabin bags (easyjet.com)
Wizz Air Help Centre, Baggage allowance (wizzair.com)
British Airways, Your baggage essentials: your baggage allowance (britishairways.com)
Jet2.com, Our baggage policy (jet2.com)
Aer Lingus, Carry-on Baggage (aerlingus.com)
Lufthansa, Carry-on baggage rules at Lufthansa (lufthansa.com)
KLM, Cabin baggage allowance (klm.com)
Air France, Authorized baggage: weight, size, and baggage allowance (airfrance.fr)
Emirates, Cabin Baggage Rules (emirates.com)
Qatar Airways, Checked and carry-on baggage allowance (qatarairways.com)
General guidance from airline, TSA and FAA rules, checked on the date shown. Rules change, and the airline and security officers decide on the day: check your airline before you fly.