Airlines’ revenues from add-ons to ticket sales jumped to almost $22 billion last year and continues to soar as more carriers chase extra sources of income, The Wall Street Journal reported.

A study released today showed that a growing number of carriers worldwide are charging passengers for services once included in ticket prices, such as baggage and food. Carriers are also finding new revenue sources, such as in-flight Internet connections and access to airport lounges that were previously restricted to loyal customers.

The study was prepared by Amadeus IT Group SA, an airline technology provider based in Madrid, Spain, along with IdeaWorks Co., an airline consulting firm based in Shorewood, Wis.

“Ancillary revenue is a growth market and it’s here to stay,” said Ian Wheeler, head of distribution and marketing at Amadeus.

The study showed that 47 of the world’s largest airlines, which account for almost half of all airline revenues, reported ancillary sales were up 38 percent from 2009. Other carriers didn’t specify how much passenger revenue they get from sources other than fares.

United Continental Holdings Inc., Delta Air Lines Inc. and AMR Corp.’s American Airlines are the top three carriers in terms of total ancillary revenues.

To see the full story in The Wall Street Journal, click here.