Talking Money: Budget when you book a trip

Chances are if you're booking a trip — whether it's a summer vacation or beyond — you're doing it online. About 80 percent of Americans use the Web to search for and book travel. Unfortunately, comparison shopping online has gotten harder, not easier. That's because airlines have started tacking on extra fees, above and beyond the cost of your ticket. Want to check a bag, board early or sit in an exit row? It'll cost you. In fact, U.S. airlines collected more than $9.2 billion in ancillary fees like these in 2010, according to the Consumer Travel Alliance.

And because these charges often show up at the gate, after you've purchased your ticket, it can be hard to get a grip on what you're actually paying. So, here's a rundown of what fees you need to look out for and where you can save.

•Beware baggage fees. By now you know that if you want to check a bag, it's going to cost you between $20 and $30. JetBlue and Southwest are the two exceptions to the rule. (JetBlue takes your first bag for free and charges $30 for the second; Southwest takes your first and second for free and charges you $50 for the next.) Clearly, traveling light is the way to go. But if you can't or won't and have many bags, you need to crunch the numbers. It may be cheaper to purchase a slightly more expensive ticket on JetBlue or Southwest and avoid the extra charge.

Be wary of extremely cheap fares. George Hobica, founder of AirfareWatchdog.com, points to the example of Spirit Airlines, which regularly advertises huge discounts — flights as low as $9 — but is, as he says, the "canary in the coal mine" when it comes to fees. They're the only carrier that charges for carry-on luggage (between $20 and $45), and they recently dropped their checked bag weight limit to 40 pounds instead of the industry standard of 50. Bags over that limit will cost between $25 and $100, depending on weight. "Quite a few (travelers) go over 40, so this is significant," Hobica says.

•Book online, but call with questions. If you book a flight by phone, you'll pay upward of $15 and often as much as $25. (Southwest, again, charges nothing.) This fee is easily avoided by booking online, but it's hard to sort through all the fees and compare costs. If you want to nail down what your final charge will be, why not pick up the phone and call the airlines directly? The customer service representative will disclose any fees you ask about over the phone. SmarterTravel.com also has a handy PDF of fees that it updates regularly.

•Skip expensive perks. Airline after airline is rolling out packages of extras — for an extra charge, of course. United has Premier Line, which allows you access to a special check-in line, a priority security line and priority boarding starting at $9. American has the Boarding and Flexibility Package, which includes group one boarding, same-day standby, and a flight change discount of $75. It, too, starts at about $9. And of course you can pay for a better seat in coach. With a family, these extra packages can add up fast, and they're often not worth the cost.

•Don't wait to get a deal. Because of gas prices, it probably isn't coming, says Anne Banas, SmarterTravel.com's executive editor. A federal projection released in mid-April said gas prices are set to jump 40 percent over last summer, and plane ticket prices are sure to follow. "Not only are they raising the base fare on a lot of tickets, they're also raising the fuel surcharge. … Your best bet is booking now rather than in June or July."

•Hold your breath until August. Almost too late for the summer-travel season, but noteworthy nonetheless, the Department of Transportation recently set some new ground rules for airlines that will take effect in August. The basics: Airlines are going to have to clearly disclose fees such as baggage charges in ads and on their websites, and they'll be required to have a bag charge refund policy, so if you paid to check your bag and it's lost or delayed, you'll have some kind of retribution. They'll also be required to include all government taxes and fees in advertised prices, which will give consumers a better idea of the total hit to their wallet. A step in the right direction, for sure.