The carrot and the stick

If you're familiar with purchasing travel online, you've certainly heard the time-worn advice to "shop around." In the ultra-competitive marketplace for airfares and hotels, that's even truer today than ever. No single website - despite the advertising that you'll hear on radio or TV - will always have all the best deals.

So it's up to you to compare prices across multiple sites - online agencies like Travelocity, providers like JetBlue, and search engines like SideStep. But what makes doing so challenging is that what you see isn't always what you get. Northwest may tout a $49 airfare on its website, but that price is for one-way travel. And the quoted fare likely won't include additional taxes and fees that can raise the actual cost of that ticket - say, from Detroit to Chicago, from $49 to a little less than $120. (Never mind that the quoted fare is probably for the days that you're least likely to want to fly.)

How you book will also affect the price of your ticket. A couple of years ago, several airlines were promoting an "online booking discount" to entice you to buy on their websites. You could think of it as a carrot (or, if you prefer dogs to horses, a rawhide bone). But a couple of months ago, most of the major airlines began to turn the online discount concept on its head. Now, if you try to book over the phone or even, egads, at an airport ticket counter, you'll be cracked with a stick and forced to pay an extra fee of $5 or $10.

That additional charge is supposed to be included in the advertised fare, according to a new ruling by the Department of Transportation. But you'll have to wait and see how the airlines implement that rule. That's because carriers don't always follow the strict guidelines that the DOT has issued about promoting airfares online, risking fines in the process.

For example, all carrier-imposed fuel and security surcharges are always supposed to be included in the advertised fare. But I've seen numerous cases where "matching" fares on multiple airlines have been promoted at different levels, even though - and here's the important part - the total price you pay will be the same.

(For example, British Airways and Virgin used to always promote fares to London that seemed to be $16 different, with one airline (correctly) considering that $16 security surcharge part of the fare, and the other carrier listing it as an additional tax. The airlines' goal, of course, is to make the price seem as low as possible so you'll be enticed to search for a ticket. With their current sales, both airlines are promoting their fares identically, and correctly. Nevertheless, a "$120" fare from New York to London is actually $344, round-trip and including taxes and fees.)

So it's imperative not only that you "shop around," but that you calculate your total price before you decide where to book. Forget about the fare you see advertised, and be especially wary of any price that starts with the word "from" (as in, "from $49"). If you're serious about finding the best deal, be sure to compare apples to apples. How much will you have to pay on your credit card for flying from A to B? That's the only question worth answering when you shop for an airline ticket.