Airlines pile on the fees

NEW YORK (Money) -- Travel alert: You'll be paying more to fly this summer on planes that are more crowded than ever - even after you've bought your ticket.

Airlines are set to fly with record full flights this summer, with air fares at their highest level since 2000. Major carriers like Delta, which emerged from bankruptcy protection Monday, are operating leaner operations, making it harder for fliers to find alternatives when there are delays and cancellations.

On top of all that, both legacy and low-cost carriers are instituting a host of fees for travelers.

A recent report by the Department of Transportation found that the average domestic air fare was $378 roundtrip, the highest level since 2000. And for airlines to survive, they may have to do even more to raise revenue.

"Airlines are constantly in search of new revenue sources," said Chris McGinnis, editor of The Ticket travel newsletter.

Travelers have gotten used to paying for food on board. But it's going to be harder to adjust to fees for services that used to be free, said McGinnis.

Here are some new or higher fees fliers are likely to encounter:

Getting a seat assignment used to be as simple as requesting an aisle or window seat. But with airlines flying at or near record load, getting a good seat is harder than ever and some airlines are betting that some fliers are willing to pay extra to ensure they don't get stuck with a dreaded middle seat.

AirTran Airways (Charts) is reportedly considering fees for advance seat assignments and $10 to $15 for reserving premium seats like those in exit rows, according to McGinnis.

That follows a move by Northwest Airline last year to charge fliers an extra $15 to reserve preferred aisle and exit row seats in coach, which have extra legroom.

Southwest Airlines (Charts, Fortune 500) CEO Gary Kelly has said he is looking for additional revenue sources beyond fares, according spokeswoman Beth Harbin. The carrier vows not to charge for things that are free now, such as a soda or a blanket. But it doesn't rule out fees for amenities it doesn't currently offer like seat assignments and meals.

And American Airlines (Charts, Fortune 500) earlier this month announced that people who do not book tickets on its Web site will have to pay a $15 fee to change seat assignments.

With fuller flights, airlines are cracking down on passengers who are carrying more than the allotted number of bags and go over the weight limit on luggage. Earlier this year, Spirit Airlines began charging fliers $10 to check in a second bag and $100 for a third bag.

Most domestic airlines now allow you to check two bags weighing no more than 50 pounds each. Go over that weight and you'll pay $25 or more per bag. If you want to check an extra bag, you'll pay up to $80 or more per bag.

Since last summer, some airlines, including United, Alaska and Northwest are charging extra for curbside luggage check in, about $2 a bag (in addition to the expected tip).

Rising oil prices are sparking another round of fuel surcharges on airlines as the busy summer travel season looms.

Friday, British Airways announced that it is hiking its fuel fee for long-haul flights by $6. Starting May 2nd, British Airways' fliers will pay $66 each way on flights longer than nine hours and $70 for long haul flights over nine hours. The fuel fee for short haul flights will remain at $16 each way.

Expect more of the same from other airlines if oil prices continue to climb higher.

In April, Northwest added a $25 fee for passengers who want to fly standby for a flight. Northwest spokesman Roman Blahoski says just 1 percent of its customers fly stand by and elite members of Northwest's WorldPerks frequent flier program and customers flying on refundable tickets will still be able to stand by for alternate flights at no cost. But for other fliers it means paying a fee for something that used to be free.

The fee-for-all formula, which has been successful for European carriers like Irish carrier RyanAir, is likely to continue in the United States. On May 24th, Skybus, a new low-fare airline based out of Columbus, Ohio, is launching with fares as low as $10 each way. But it will be charging for virtually everything including each checked bag ($5 for the first two bags, $50 for a third), priority boarding ($10) as well as food, drinks, blankets and pillows.