But those fees don't have to be a mystery. Whether you're the king of checking baggage or the queen of changing tickets, whether you like your blankets free or don't mind packing your own snacks, knowing what an airline will charge to match your style can matter as much as where you fly.
Recognize How You Fly
As someone who often travels with only carry-on luggage, I have yet to pay a checked-baggage fee. But had I flown Spirit (SAVE), my carry-on-only policy would have backfired. While many airlines will allow a small carry-on item and one personal bag free of charge, the sizes and weights of the items allowed vary widely by airline. Spirit and Allegiant (ALGT), meanwhile, are the only two airlines in the United States to charge for carry-ons. Spirit recently sparked a backlash over its decision to raise its fee for carry-on items checked at the gate to $100.
Need to change your ticket? Get hungry on a flight? Tend to get chilly? Everything is fair game for a fee, from rebooking to snacks to blankets and pillows, and there is no industry standard.
Adding Up the Whole Bill
While some discount-airfare websites are great at comparing fares, they do little to show you the actual cost of your flight. It's not the websites' fault; airlines routinely refuse to release this information to travel sites, denying customers a full picture of what they'll pay. But most of the information is out there if you know where to hunt, and researching it can pay off.
'Getting There' Means More Than Landing at the Airport
Once you've found a flight that suits you, sorted out what you'll need to get through the airport, and checked into your flight with the least amount of hassle and cost, there's one last thing you might want to consider: what you'll do once you get there.
Few things are worse than going to a lot of trouble to save money on airfare only to spend it all on a cab getting to and from your hotel or final destination. If you're heading to an urban area, check to see if there are subway, light rail, or other mass-transit options. Cheaper than a cab, these options are often also faster, especially if you're traveling underground when the streets above are frozen by gridlock. Time it right, and you may even get to your hotel in time for the early-bird dinner.
Molly McCluskey doesn't own shares in any airlines or travel companies. Follow her finance and travel tweets on Twitter at @MollyEMcCluskey.