Since 2008, the three U.S. legacy carriers have been adding more and more fees.

These are all the hidden fees to avoid, and how United, Delta, and American compare.

But following American Airlines decision to charge checked bag fees for domestic flights, everything changed.

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With United, youll pay $35 for a carry-on the same as a checked-baggage fee on domestic flights.

That comes to $60.

kids who fly on their parents lap)flew for free.

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Thats almost 18 percent of my adult fare.