NBC (WILX) - They come in all shapes and sizes and earn the airlines a lot of money.
Companies brought in early $5 billion in baggage fees last year.
"Usually the first bag costs about $30, the second bag costs $40, so if you're traveling with a family, it can add up to hundreds of dollars," said Liana Corwin, Hopper travel consumer expert.
Here's how to avoid the fees if you're not flying business or first class:
You could fly Southwest where bags do fly free.
The ticket may cost more, but the free bags could make it worthwhile.
Always weigh your bags at home.
If you're even a pound over the 50-pound limit, you could pay an extra $100 at the airport.
Join an airline mileage club.
Elite status means no luggage fees.
Get an airline credit card which can allow two free bags per trip, plus a companion's bags.
That's up to $200 in savings.
You could also avoid checking bags by stuffing it all into a carry-on.
Finally, you can save by paying for bags in advance, rather than at the airport.
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