AIRFARE REPRESENTS a mere fraction of the total cost to fly these days. From the time you walk into the terminal until the plane lands, your total tally will be far greater than the quote you received from Expedia while booking the flight.

"Every week, it's a different airline and a different fee," says Anne Banas, executive editor for travel advice site SmarterTravel.comOnly Southwest Airlines, which locked in gas prices eight years ago, remains comparatively fee free.)

Looking for ways to make up for those losses without scaring off customers by raising fares airlines now charge for the most basic amenities. "We are truly going to an a la carte system," says Tom Parsons, CEO of discount airfares site BestFares.com. "It's down to the nickel and dime from here on out."

For consumers, the best defense is to factor in the fees each airline charges when comparing fares, says Banas. Here are seven instances when fees are assessed and how to avoid them:

Booking

Except Southwest, every major airline charges a fee to book a flight over the phone. The worst offenders:

Delta Air Lines

United Airlines

Orbitz

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Redeeming Frequent-Flier Miles

"Some people have been collecting miles for years, and now they have to pay extra to use them," says Parsons.

US Airways

American Airlines

Choosing a Seat

Opt to stretch out in an exit row, and it'll cost you.

AirTran

Changing a Ticket

Alaska Airlines

Continental

Curbside Baggage Check

Don't feel like rolling the suitcases inside the terminal? It'll cost you.

Northwest

Checking Bags

When it comes to checking luggage, it's a virtual fee-for-all, warns Banas. American, Northwest, Spirit, United and US Airways all charge $15 for the first checked bag. And while Delta announced it would stand firm against invoking such a fee, it's doubled charges for checking a second bag to $50. Think you can avoid the second bag fee by stuffing everything into one case? Be warned, it may end up costing even more. Going just one pound over the 50-pound limit triggers an overweight fee of $29 (AirTran) to $125 (United). Stick to carry-ons (although be prepared to fight for space) or ship extra-heavy bags to the hotel ahead of time to avoid these fees. (See more tips on

In-Flight Amenities

Forget about relaxing with a soft pillow and a cold drink. Only a few holdouts, including Continental and

JetBlue

Also See:
10 Things Your Airline Won't Tell You
How to Avoid Paying Airline Baggage Fees
Sites Allow Frequent Fliers to Swap Miles for Cash, Other Awards