Carry-On Size Limits by Airline: The Numbers Every US Carrier Publishes

The number most US airlines publish for a carry-on is the same number: 22 × 14 × 9 inches. American, Delta, United, Alaska, JetBlue and Hawaiian all state it on their own baggage pages, and all of them specify that it includes wheels and handles. Southwest publishes a larger allowance, and the ultra-low-cost carriers publish their own figures alongside a fee.

That is the part everyone agrees on. The part that trips people up comes later, when the bag they bought — sold as “carry-on compliant” — turns out to be an inch over in one dimension.

What each airline publishes

Airline	Carry-on limit (in)	Personal item (in)	Weight limit
American Airlines	22 × 14 × 9	18 × 14 × 8	None enforced on most fares
Delta Air Lines	22 × 14 × 9	Not published as dimensions	None enforced on most fares
United Airlines	22 × 14 × 9	9 × 10 × 17	None enforced on most fares
Alaska Airlines	22 × 14 × 9	Not published as dimensions	None enforced
JetBlue	22 × 14 × 9	17 × 13 × 8	None enforced
Southwest	24 × 16 × 10	Under-seat only	None enforced
Spirit	22 × 18 × 10	Small personal item	40 lb
Frontier	24 × 16 × 10	Small personal item	35 lb

Figures are those published by each airline on its own baggage information pages. Check your fare before you rely on any of them: basic economy on American, Delta and United restricts the overhead carry-on, and on some routes a bag that meets the dimensions still gets gate-checked because the bins filled.

Why your bag’s spec sheet disagrees with the airline

Two reasons, both common.

The brand measures the shell; the airline measures the bag. Manufacturers frequently publish the body dimensions and list wheels, handles and external pockets separately, or omit them. Airlines measure the whole thing at its widest points. A “22-inch” bag with a 2-inch wheel housing and a flush handle is often 23 or 24 inches as the airline measures it.

Sources disagree with each other. Published dimensions for the same suitcase vary between the brand page, retailer listings and third-party reviewers — sometimes by more than an inch in a single dimension. When you see two different figures for the same bag, the larger one is usually the one that includes everything protruding, and that is the one that matters at the gate.

The practical rule: measure your own bag. Extend the handle, stand it on its wheels, and take the number at the outermost points. If that number is over the airline’s figure, the bag is over — regardless of what the product page says.

The regional jet problem

A bag that fits a mainline overhead bin can fail on a regional jet. Embraer 175 and CRJ-series aircraft have smaller bins, and roll-aboards that pass the sizer are routinely gate-checked on those aircraft anyway. Soft-shell bags have an advantage here: they compress. A hard-shell case either fits or it doesn’t.

What actually gets enforced

US carriers rarely measure bags at the gate. The airlines that do enforce dimensions and weight consistently are the European budget carriers — Ryanair and Wizz Air keep sizers at many gates and charge at the gate — and Spirit and Frontier, for whom carry-on fees are revenue. Several Asian carriers enforce weight rather than size.

None of this means the limit doesn’t apply. It means the risk is asymmetric: a bag a little over the line usually sails through on a US domestic flight, and usually doesn’t on a budget carrier in Europe.

Measuring before you buy

If you’re choosing a bag rather than checking one you own, the useful number isn’t the capacity in litres. It’s the external footprint with wheels and handles included, compared against 22 × 14 × 9. Capacity figures are useful for deciding between two bags that already fit; they say nothing about whether either one does.

Three cases, three footprints

It helps to have reference points, so here are three that sit at different places on the range.

Away The Carry-On publishes 21.7 × 13.7 × 9.0 inches — inside the standard limit on paper, with a textured shell that hides scuffs better than glossier finishes. The recurring complaint in long-term owner reports is handle wobble after heavy use.

Monos Carry-On Pro publishes 22.0 × 14.0 × 9.0, which is exactly the limit rather than under it. Its Hinomoto wheels are the part reviewers single out, and the front laptop compartment means security without unpacking — though that compartment is space taken out of the main cavity.

Travelpro Maxlite 5 21” publishes 21.75 × 15.75 × 7.75 — the widest of the three and by far the lightest at roughly 5.4 lb. Fabric compresses, which matters on regional jets, but there’s no rigid protection for anything fragile.

Published dimensions for all three vary between sources by up to an inch in a single dimension. That variance is itself the argument for measuring the bag you actually receive rather than trusting any listing.