Carry-On Weight Limits by Airline

“None published” means exactly that: the carrier publishes a size rule and no weight rule. It is not a guarantee that a very heavy bag will never be questioned at a gate.

Why most US carriers do not publish one

The overhead bin has a structural load rating, but airlines have historically managed that by limiting the number of bags rather than the weight of each one, and by relying on a self-selecting constraint: you have to lift the bag over your head. JetBlue says this almost in so many words — it states plainly that it has no carry-on weight restriction, but that you must be able to lift the item into the bin without assistance.

International carriers behave differently. Ryanair caps the cabin bag at 10 kg, easyJet at 15 kg, British Airways at 23 kg — all published, all enforced with scales at the gate more often than any US carrier does. If your itinerary includes a European short-haul leg, the weight rule you have never thought about is suddenly the binding one.

How much of the cap the empty bag spends

A published weight limit is not really an allowance for what you pack — it is an allowance for the bag plus what you pack. On Hawaiian’s 25 lb cap, the choice of suitcase decides how much of that you get to use, and the spread is large.

The difference between the lightest and heaviest bag here is 6 lb of payload — roughly four days of clothing. On a carrier that publishes a weight limit, the bag you choose is worth more than the packing technique you use.

What this means in practice

• If you never fly a carrier with a published cap, weight is still worth optimizing, but for your shoulder rather than for a rule. Carrying a 9.3 lb empty case through a terminal is a real cost even when nobody weighs it.
• If Hawaiian is in your rotation, treat 25 lb as the real constraint and buy the lightest bag that still fits the box — we rank exactly that.
• If you fly Frontier, Breeze or Sun Country, the 35 lb cap is generous enough that most people never touch it — but you are already paying for the overhead bag on those carriers, so the free personal item is usually the better play.
• If you have a European leg, check that carrier separately. Ryanair’s 10 kg is 22 lb — less than Hawaiian’s cap and applied to a much smaller bag.

Weighing a bag without a luggage scale

Stand on a bathroom scale holding the packed bag, note the figure, put the bag down and weigh yourself again. The difference is the bag. It is accurate to within a pound on any digital scale, which is more precision than any gate enforcement applies, and it costs nothing.

Do it once with a fully packed bag and you will know roughly what your normal packing weighs for good. The number is usually lower than people expect for clothing and much higher than expected for anything with a battery, a book or a pair of shoes in it.

The international picture

Note that the weight allowance and the size allowance are not correlated. British Airways publishes the most generous weight cap here at 23 kg and a cabin-bag box similar to Southwest’s. Ryanair publishes the tightest weight cap and the tightest box, and charges for the overhead bag on top.