Source: Christopher Elliott, Special to USA Today

Many airlines, especially discount carriers, quote a dirt-cheap base fare. But if you want to check a bag or just a carry-on bag, the cost of your fare can easily double.

If you think that's bad, wait until Congress passes the FAA Reauthorization Bill, which funds the Federal Aviation Administration. The version being considered by Congress has a provision that would rescind a full-fare advertising rule that requires airlines to quote an airfare that includes all mandatory taxes and fees.

NetVoucherCodes found Spirit Airlines hid the cost of flying the most, with the average flight cost soaring by 736%. Frontier ranked No. 3, and Delta Air Lines was the worst-performing legacy airline at No. 5, with an average increase of 158%.

Read Full Article: Airlines are hiding the cost of air travel