No matter your weight or your width, the next time you fly make sure you know your airline’s policy on “seatmates of size.”  Better yet, if you can find your airline’s customer of size policy, print it out and carry it with you.

It may help you avoid a pain in the butt and it may save you some bucks.

Last week, United Airlines laid out its new policy for “Passengers requiring extra space.”  It says that passengers who can’t fit into a single seat in their ticketed cabin; need more than one extender in order to buckle their seatbelt and; are unable to put the seat’s armrest down when they are seated may have to purchase a second seat if there are no extra empty seats on their scheduled flight.

What’s the policy on other airlines?  Find out in my Well-Mannered Traveler column posted today on MSNBC.com:  What a deal: one person, two fares.

You may surprised.  Some airlines don’t post their policies and just say they’ll “work something out” if a passenger can’t fit in one seat. Other airlines are very specific about their rules and make it easy to find them – but you may not like what you read.

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