In my years of traveling, even on budget carriers, I’ve been lucky: only once has a gate agent challenged the size of my personal item.
I was on a Northwest Airlines (RIP—it was acquired by Delta) flight to Hawaii with a layover in Seattle. As I was reboarding for my second leg, an agent asked to check the size of my backpack. I did, and they told me it was too big, even though it had just fit under the seat on my first flight... on the same plane.
Fortunately, I was able to redistribute some items among my travel companions, but I was struck by the arbitrariness of the policy and how it was enforced.
These days, things aren’t much different. There's still no industry standard for personal item size and rules vary by several inches between carriers, even when the plane is the same. A bag that may have been waved through on a United A320 may get stopped as you try to board a Frontier A320.
To avoid gate checks and unexpected charges, your best bet is to understand dimensional limits, enforcement tactics, and what counts as a personal item before you leave for the airport.
In this article
What Counts as a Personal Item
A personal item differs from a carry-on bag in terms of both what it costs to bring along and where you’re typically required to stow it when onboard an aircraft.
Carry-on baggage is usually stowed in an overhead bin, while a personal item must be small enough to fit entirely underneath the seat in front of you. As such, personal items can be things like purses, backpacks, briefcases, or laptop bags.
Importantly, a personal item is the only thing you can bring on board free of charge, in any fare class, on any U.S. airline. This is likely why carriers can be so strict about their personal item policies. It also comes into play when you’re deciding whether you’ll need to check a bag.
The Size Range Across Major U.S. Carriers
A bag that’s fine on one carrier may be considered an oversized personal item on another.
American Airlines allows bags up to 18 by 14 by 8 inches, which is one of the more generous allowances among airlines. But, United Airlines limits personal items to no more than 17 by 10 by 9 inches. JetBlue’s limits are 17 by 13 by 8 inches. Delta doesn’t have a strict sizing policy, but personal items must fit beneath the seat in front of you.
Southwest, likewise, doesn’t publish dimensions for personal items but requires them to fit under seats.
Budget Carriers Have Stricter Rules
While major carriers often allow a free carry-on bag for non-basic economy fares, some more affordable budget airlines typically charge for any bag that’s not considered a personal item, i.e., a carry-on.
So if you don’t want to pay a luggage fee, it’s important that you know your airline’s allowances and comply with them before you arrive at the airport.
Frontier Airlines and Allegiant Airlines both allow personal items up to 18 by 14 by 8 inches. Breeze Airways’ allowance is smaller, at 17 by 13 by 8 inches. On these airlines, you can get slapped with an exorbitant gate fee, often more than your ticket cost, if your personal item doesn’t fit.
It’s never a bad idea to aim small, as carriers can change their allowances without notice, bumping their chances to net additional baggage revenue.
How Gate Enforcement Works
Gate agents rely on bag sizers placed conspicuously near the boarding door to measure personal items and ensure they comply with the carrier’s policies.
Even so, enforcement can be subjective, depending largely on the gate agent who checks you in and how full your flight is.
If your overstuffed bag looks like you could cram it beneath a seat on an undersold flight, you may get waved onto the jetway. If you’re booked on a packed flight or flying a budget carrier, however, an agent may ask you to drop your bag into a sizer. You can be charged or asked to gate check your bag if a single strap or wheel protrudes from the sizer.
Always prepare for the worst, as enforcement varies wildly among carriers, gate agents, and even day-to-day. To be safe, pack a smaller bag inside your personal item that you can fit essentials in, just in case you're ever forced to part ways with your bag.
International Carriers
All bets are off when it comes to choosing luggage for travel on non-U.S. carriers, which can make packing feel like a game of Tetris.
Some carriers, like Lufthansa, Air France, Japan Airlines, and Aeromexico use combined weight limits, adding the heft of your carry-on and personal item together, rather than or in addition to measuring dimensions. If the combined weight exceeds limits—for example, a maximum of 22 to 33 pounds together on Aeromexico, depending on your fare—you’ll be subject to fees.
European budget carriers are also notoriously strict when it comes to dimensions for their personal item allowances.
Ryanair, for example, caps small bags at 15.75 by 11.81 by 7.87 inches, while easyJet allows personal items up to 17.7 by 14.2 by 7.9 inches. Be sure to know the metric dimensions of your bag and your carrier’s allowances before you get to the airport.
The Shortcut
While most U.S. airlines follow a general rule that a personal item must fit beneath the seat in front of you, some are strict and measure bags at the gate. Measure your bag with the handles, wheels, and straps included, because they count toward the total dimensions if placed in a gate sizer.
United Airlines is the most restrictive major carrier at 17 by 10 by 9 inches, so sizing your bag to this limit ensures it will clear most other airlines.
International carriers often enforce combined weight limits for all cabin baggage, so check their guidelines and use metric measurements rather than relying on U.S. standards.
