United Airlines Checked Baggage

United caps a standard checked bag at 50 pounds in economy and 70 pounds in business, first and Polaris. It will not accept anything over 100 pounds at all. That single number drives most of the United checked baggage policy, since United treats the fee, the size box and the connecting bag rule as three separate questions.

United checked baggage policy does not publish one flat price for the first or second bag. Instead it runs each fare through a baggage cost calculator. The price depends on the route, the cabin and when the ticket was bought.

This page sticks to what United states outright: the size box, the weight tiers, what triggers an oversize or overweight charge, and how a connecting itinerary is handled. For the carry-on side of United’s rules and the headline fee figures, see this site’s main United Airlines baggage guide.

The size and weight United actually enforces

A standard checked bag can measure up to 30 by 20 by 12 inches. In centimeters that is 76 by 52 by 30. United totals it as 62 linear inches, including the handles and wheels.

Anything within that box and under the weight cap for your cabin ships as a standard bag.

United applies whichever limit is larger when a cabin and a status limit disagree. A Premier Gold flying economy still gets 70 pounds. That is worth knowing before you pack.

When a bag becomes oversized, overweight or extra

United will not accept a checked bag once its length, width and height add up past 115 inches. In centimeters that is 292. Below that line but above the standard 62 inch box, the bag ships as oversized for an added fee.

The absolute weight ceiling is 100 pounds, or 45 kilograms. United makes two exceptions: musical instruments up to 165 pounds, and assistive devices at any weight, carried free. A third or later bag counts as an extra bag, and United only carries one when the flight has room.

For the full detail on how United sets these charges by route and ticket date, its own checked bags page is the source. This site’s own overweight and oversize baggage fees guide shows how those bands tend to compare across carriers.

What cannot ride in the hold

Beyond the FAA’s own restricted list, United keeps a separate dangerous items catalog. It covers batteries, smart bags, lighters and rideable suitcases. A smart bag with a lithium battery that cannot be removed is not accepted as checked baggage at all.

The battery has to come out and travel in the cabin, or the whole bag has to travel as a carry-on instead. This site’s guide to batteries in checked luggage covers the lithium rules that apply across most US carriers.

Firearms are allowed in checked bags when unloaded and secured in a locked hard case. They also have to be declared at the counter.

Connecting flights and partner airline bags

On most connecting itineraries, United checks a bag straight through to the last stop on the ticket. You only collect it once. You still have to claim and recheck it yourself in a few cases.

An overnight layover is one. A next flight leaving more than 12 hours after you land is another, as is switching to a separate ticket on a carrier outside Star Alliance.

Whoever operates the first segment of a mixed itinerary generally sets the bag fee for that leg. Fly a partner airline first, and United says that carrier’s own policy applies. A MileagePlus Premier or United credit card waiver may not carry over to that segment, so check both carriers.

See how connections work on other airlines in this site’s connecting flights guide.

How strictly the counter enforces the limit

Frequent flier discussion of United checked baggage policy is fairly consistent on one point. Every bag gets weighed at the counter or the bag drop, not spot checked. Travelers who show up close to the cap describe being asked to shift items into a carry-on on the spot, not waved through.

Nobody in that discussion described United pooling weight across two checked bags. A 60 pound bag and a 40 pound bag are each judged on their own, not averaged together. Weigh your bag the night before if you are anywhere near 50 pounds, since repacking in the terminal wastes more time than doing it at home.

The same threads mention that a bag right at the line, say 49 or 50 pounds even, usually goes through without argument. It is the bags a few pounds over that draw a second look and a request to open the case. This site’s checked baggage weight limit guide has more on how airlines round and where they draw that line.

Checked cases that stay under United’s cap

A lighter empty case leaves more of that 50 pound allowance for what you actually pack. That matters more under United checked baggage policy than the sticker size of the suitcase. The Etekcity digital luggage scale settles the question at home before it becomes a counter argument.

If your fare only includes a carry-on, or if the overhead bins fill before you board, it is worth knowing your box on the cabin side too. This site’s United carry-on size guide covers that box and the fares that drop it entirely.

The bottom line

United checked baggage policy is really two rules stacked together. There is a 62 inch, 50 pound standard bag. Past that point, a calculator prices things by route and date, not a flat chart.

Pack toward the lighter end of your cabin’s weight limit. Check the first segment carrier on a mixed itinerary, and weigh the bag at home rather than at the counter.

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