TIME’s most recent issue included a piece on add-on charges on airfare, which last year created $21.5 billion in revenue for airlines. These add-on fees, or a la carte fees, are an approach that airlines have increasingly used to circumvent fare wars and continue to improve profits ahead of rising gas prices. This approach is called “unbundling”, or taking those products and services that were considered part of the regular price of the fare and charge separately for each one.

            One might think that a la carte pricing is a better way of flying. Afterall, instead of paying one fare for all of the amenities, whether you use them or not, you are instead paying for only those services that you actually use (plus the price of the trip, of course). However, unbundled service fees are well-above the comparable price of the old single fare. In fact, according to TIME, profit margins from add-on revenue are as high as 80%. Many airlines now see the potential for major growth in unbundling, and air travelers can expect to see this because standard practice among large and small carriers.

            Here are some common unbundled services:

-       Waiting in line: Airlines will charge a fee for passengers to move to the head of the line so that they are guaranteed an overhead bin. Kind of a de-hassle fee. Expect to pay $10 - $35 for this perk.

-       Leg-room and Exit-rows: Just like real estate, carriers are now charging added fees depending on where one sits in coach. Thos seats with added legroom, and seats in exit rows or near the bulkhead, are an extra $5 to $49.

-       Pillow and blanket: Remember when these were free? Not anymore. $7

-       Meals: See above. $5 to $10

-       Pets: To bring along you furry friend could cost you as much as $125 one way.

-       Wi-Fi: To get you wireless access in-flight you’ll need to pay $5 - $15.

-       Baggagge: Most of us are familiar now with baggage fees, and not just for overweight bags. The first checked bag will cost you $25, Check another and it’s $45. Southwest and JetBlue don’t charge for bags.

As unbundling becomes the standard way of doing business, consumers are inevitably going to become frustrated with sorting out all of the fees and knowing who charges for what. Some of the larger, more expensive airlines are counting on that. If you don’t do your research you could wind up purchasing a ticket that has an attractive low airfare, only to find out at the gate that you’re getting slammed with add-on fees that double the base price. The best way to go is to simply check up on the airline to see what they charge for and what they don’t. (The U.S. DoT is trying to help us out here, making airlines more transparent with their add-ons.) Also, if your dates are flexible and you can afford it, book on a blind-sight discount website like Travelocity or Orbitz. I recently found incredibly low fares on off week-days to Maine, which will help to off-set the pain at the counter.