Airlines' ancillary revenue rose to $22.6 billion in 2011, according to an IdeaWorks study sponsored by Amadeus.
In 2009 and 2010, airlines collected $13.2 billion and $21.5 billion., respectively, according to IdeaWorks.
IdeaWorks researched financial filings by 50 airlines worldwide that report ancillary revenue. Six American airlines were in the top ten in 2011.
United Continental collected the most: $5 billion, nearly twice what Delta collected, about $2.5 billion. American followed with $2 billion. Southwest collected $1.14 billion, US Airways collected roughly $1 billion and Alaska Airlines collected nearly $600 million.
Southwest, which prides itself on being a relatively fee-free airline (you can check two bags for free on Southwest) collected $142 million on its EarlyBird service, which lets passengers board early for $10.
Ancillary fees can start at as little as a $1 or so to have a flight itinerary sent to a mobile phone. They increase from there and can include paying for the privilege to board early in order to get overhead storage bin space, seat selection, onboard dining and entertainment, and checked bags.
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