Paying 'Less' For A Plane Ticket? Check The Baggage Fee.

If you think you've scored a "cheap" plane ticket, take another look to be sure.

Checked-bag fees can add major costs to your trip . But many travelers often fail to realize that cheaper, "low-cost" airlines are sometimes where you'll wind up paying high prices in checked-bag fees.

Spirit Airlines, known for its super-low fares , charges those outside its "fare club" $30 to $100 per checked bag  depending on how the tickets are booked, per the Business Insider guide  below. When the average price to check your first bag is $25, that's not such a stellar deal.

And be careful with some budget airlines abroad: On easyJet , you'll pay about $18 to $34 if you register your checked bag online. But make the mistake of waiting till the airport, and the price will be anywhere from about $50 (at the bag drop area) to about $70 (at the gate) . 

In short, budget airline fees can really get you down you if you don't plan ahead.

Of course, there are exceptions: Southwest is a winner in the baggage department, where both the first AND second checked bags fly free. And JetBlue -- which only recently started charging for checked bags  -- costs $20 if you check in online or at a kiosk.

Want to know how much your next trip will really cost, all fees considered? Check out Business Insider's guide  below.

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