Get the most out of your frequent flier miles

(Tribune Media Services) -- Using your frequent-flier miles to get to Europe can save you a bundle, if you know the ropes and plan ahead.

What began as a way to reward customer loyalty has evolved into a profitable side business for the airlines, who sell "award miles" to credit card and other companies (who pass along those miles as incentives to their own customers). Here are some strategies for getting the most travel out of your miles. For more tips, check out www.flyertalk.com.

Book as far ahead as possible. Airlines reserve only a handful of "award seats" on each flight -- and once they're gone, they're gone. Even if the "award seats" are booked up, you can sometimes use additional miles to get on the flight (for a first-class seat, or for a double-miles "rule-buster" seat -- though these are being phased out). In short: The farther ahead you book (ideally several months in advance), the more likely you'll get your choice of flights for the fewest miles.

Maximize the miles you earn. I'd never fly on a particular airline just to get the miles. For me, the price and convenience of a flight plan always trumps the potential for netting miles. But if you're flying anyway, many figure you might as well get all the miles you can. For example, booking direct with the airline, rather than on a third-party booking site, might earn you bonus miles. Some credit cards allow you to accrue miles with each purchase (sometimes with an annual fee).

Know about alliances. Most major airlines belong to one of three gigantic frequent-flier collectives. For example, the Star Alliance includes North American airlines (United, US Airways, Air Canada) as well as European carriers both big (Germany's Lufthansa, SAS Scandinavian, LOT Polish Airlines, Spainair) and small (TAP Air Portugal, Croatia Airlines, Slovenia's Adria Airways). Other alliances include SkyTeam (Northwest, Continental, Delta, KLM, Air France, Alitalia, Czech Airlines) and OneWorld (American Airlines, British Airways, Air Iberia, Finnair, Malev Hungarian).

If you have miles on any airline in the alliance, you can redeem them on any of the others. So, for example, if you're headed to Prague, try using your Northwest miles first (allied with Czech Airlines); for Helsinki, see what you can get with your American miles (partnered with Finnair); and for Croatia, check with United (allied with Croatia Airlines).

Use airline alliances to collect miles smartly. The same alliances work for collecting miles. You might not care about earning miles for an SAS or Air Portugal flight, but if you give them your United frequent-flier number, the miles go into your United pot.

To redeem your miles, check online first, then call. Check if the flight you want is available on the airline's "miles redemption" site. If not, don't give up. Call to speak with an airline agent. While this can come with a small additional fee, it's worth it to talk with a live person who has all your options at his or her fingertips -- especially if you...

Do some research and know your options. There are a variety of ways to connect any two points. When you try to redeem miles, the agent might simply try the most straightforward route. If that route is sold out, ask them to check other ways. Better yet, do some homework before you call, and make a list (in order of preference) of the connections that would work for your trip. For example, if I'm going from Seattle to London, it's easiest to take a direct, nonstop flight. But if that's full, I'd be willing to settle for any one of the dozens of other possible connections through other cities.

Buy or transfer miles. If you have almost, but not quite, enough miles for the trip you want, look into the option of buying miles from the airline, or paying a fee to transfer them from someone else (e.g., a spouse or relative). While it obviously wouldn't be cost-effective to do this for the entire value of a ticket, if you're 2,000 miles short on the 50,000-mile fare, buying or transferring miles can bring it within your reach for a relatively small cost.

Watch the expiration date. For many airlines, miles expire at a certain point after you accrue them (usually one to two years). Know your miles' shelf life, and use them before they're gone. Typically the miles must be used for a ticket before the expiration date -- but the flight can occur anytime, even months later.

You're still responsible for taxes and some fees, but it's still a fraction of the full fare.

If airline miles help you afford to fly, using them smartly can help you actually fly more frequently. Happy travels!

Rick Steves writes European travel guidebooks and hosts travel shows on public television and public radio. E-mail him at rick@ricksteves.com, or write to him c/o P.O. Box 2009, Edmonds, Wash. 98020.

Copyright 2007 RICK STEVES, DISTRIBUTED BY TRIBUNE MEDIA SERVICES, INC. E-mail to a friend