United Baggage Allowance: Sizes, Weights, Fees

United's carry-on can measure up to 22 by 14 by 9 inches, and that figure includes the wheels and handles, not just the case body. United does not publish a weight limit for the carry-on, but the bag still has to fit in the overhead bin sizer at the gate, so a light bag that is simply too bulky will still get pulled and checked.

Your personal item, a purse, backpack, or laptop bag, has its own limit of 9 by 10 by 17 inches and has to fit under the seat in front of you. Most fares allow one carry-on and one personal item together, both free. Measure your actual bag against these numbers with the fit checker before you leave for the airport, since a bag that looked fine on the manufacturer's listing can still run over on one dimension.

United enforces the 22 x 14 x 9 inch limit with a physical sizer at select airports, not just a stated number on a webpage, so a soft-sided bag that compresses slightly under its own weight has more margin than a rigid hardside case built to exactly 22 inches. If your bag is borderline on one dimension, that construction difference can matter more than the spec sheet does.

This is where people get caught out most often. On domestic United Basic Economy and most short-haul itineraries, you're only allowed the personal item. The full-size carry-on is not included, and if you show up with one anyway, United checks it at the gate for a fee.

There are real exceptions. Basic Economy tickets on flights to South America, and on transatlantic or transpacific routes, still include the full carry-on. MileagePlus Premier members and holders of qualifying United co-branded credit cards keep the carry-on regardless of fare. If none of those apply to your domestic ticket, plan around a personal item only, or upgrade out of Basic Economy before you fly.

It's worth separating two different kinds of check-in you might run into on United. A bag that's gate-checked for space reasons, because the overhead bins filled up before boarding reached your group, is free. A bag checked because your Basic Economy fare doesn't include a carry-on at all is the one that costs money. Same result at the jet bridge, completely different reason and price.

Standard checked bags in United Economy and Premium Economy can weigh up to 50 pounds and measure up to 62 total inches, length plus width plus height, wheels and handles included. Business, First, and United Polaris business class passengers get a higher 70 pound allowance per bag.

United has hard ceilings above which it will not take your bag at all, 100 pounds and 115 total inches. Past those numbers you're not paying a bigger fee, you're arranging cargo shipping or leaving the item behind. Musical instruments and assistive devices are the only stated exceptions, accepted up to 165 pounds.

These figures apply per bag, and United doesn't publish a separate total-piece cap for domestic checked baggage beyond the practical limits its fee tiers create. If you're checking more than two or three bags on one ticket, it's worth confirming directly with United, since multi-bag itineraries can bump into airport-specific handling limits that don't show up on the standard fee page.

Search how much is a checked bag on United and you'll find a number on nearly every travel blog, and a lot of them are wrong or stale. United's own baggage page says plainly that fees depend on when you bought your ticket and where you're flying, and it points you to a baggage fee calculator instead of listing a rate. That schedule changed at least twice in 2026, once on April 3 for domestic flights and routes to Latin America, Canada, the Caribbean, and Mexico, and again on May 12 for many flights to Africa, Asia, Europe, and South America.

The one flat figure United does publish is unrelated to your normal checked bag allowance. If you end up traveling with a carry-on you're not entitled to, typically a domestic Basic Economy passenger, checking it costs $50 at the airport lobby or $75 if you wait until the gate, for tickets bought on or after April 3, 2026. That's a penalty for a disallowed carry-on, not the price of your first standard checked bag, and it's worth not mixing the two up.

The practical workaround for the how much is a checked bag question is to run the actual numbers yourself: start a mock booking or log into Manage Reservations for your real route and dates, and the calculator shows the fee before you pay anything. Any flat number quoted without that context, including ones on competing sites, is at best an estimate for a specific route on a specific day, not United's general policy.

A bag between 51 and 70 pounds counts as overweight, and one that stretches past 62 total inches counts as oversized. United says both charges apply if a bag is both overweight and oversized, but again, no static dollar amount appears anywhere on the checked-bags page. The number comes from the calculator at booking or check-in.

International routes add their own variation, since allowance and fee schedules differ by destination region, and the same calculator handles those differences too. If you're flying United internationally, check the calculator for your specific route before you pack, because a bag that would sail through domestically can trigger a fee on an international itinerary.

One distinction worth keeping straight: the 50 pound standard limit is a soft ceiling with an overweight fee attached, while the 100 pound and 115 inch marks are hard ceilings where United won't take the bag no matter what you're willing to pay, short of arranging air cargo shipping separately.