1. Search at the Right Time
Try hunting for fares after midnight; that's when many airlines reload their computers with the deeply discounted fares that people reserved but didn't pay for. If you're only seeking last-minute Web fares, look on airline sites, major booking sites, and aggregator sites (search engines that scour on-line suppliers, consolidators, and booking sites) between Tuesday afternoon and Wednesday morning for tickets for the coming weekend. Such fares usually require that you leave on a Saturday and return on Monday or Tuesday, but some airlines offer Friday departures and Sunday returns.
2. Check a Broad Range of Dates
Travelocity and Orbitz have the most flexible search functions of any of the major booking sites. Travelocity will allow you to search for the lowest round-trip or one-way domestic or international fare within a range of months, which it shows as green dates on a calendar. Even if you are just using Travelocity's calendar for research, click all the way through an available date; the site frequently shows dates as available when they're actually sold out. Orbitz will let you search for the lowest price over a weekend you designate; search up to three days before and after your dates; or look for the lowest published fare within a 30-day period. The site recently extended its flexible search option to include international flights, though at press time, it still indicated that the destination airport "must be within 50 U.S. states, Puerto Rico, U.S. Virgin Islands, or Canada." Expedia's flexible search provides a pull-down list of 50 popular U.S. destinations only.
3. Use Aggregator Sites
Once you've figured out which dates will yield you the best fares, search one of the Web's "meta" travel agents. Mobissimo searches 85 U.S. and international sources and converts foreign currencies to U.S. dollars. Kayak, which at press time was still being tested, searches 60 sites and allows you to sort airfare results by departure or arrival time. Qixo is a good source for deals from small charter companies and discount airline agencies, as well as major carriers—28 in all. Cheapflights lets you search flexible dates and, like Travelocity, offers a calendar with a range of available dates. Here, too, you should click through the green (available) dates to ensure that the fare you want isn't sold out. Aggregator sites don't charge fees themselves, but they might direct you to a site that does.
4. Book Award Tickets Early—and On-line
Since airlines allocate only a small percentage of their seats for award travel, it's smart to book months in advance. Just to be safe, book 330 days in advance—when most airlines load award fares. Also, reserve those seats on-line: American, Northwest, and Continental all charge $5 for booking award travel over the phone and $10 for doing it in person—but nothing for on-line reservations. (United charges more to book award travel by phone than to book paid tickets by phone: $15 versus $5.) If you do get lucky and are able to reserve an award seat only a week or two before you travel, unfortunately you could get slapped with a high "expediting fee." For instance, Delta charges $50 within two weeks of travel; Continental charges non-elite frequent fliers $75 for booking within three days of flying (elites pay $50).
5. Book Through an Airline's Web Site
If you've found the same low fare on an on-line booking agent like Orbitz and an airline's own Web site, it makes more sense to reserve on the latter to avoid paying the $10 or so service fee booking sites now charge. By booking on an airline's site, you'll also avoid the service fees the airlines themselves have begun to charge: $5 for booking over the phone, and $5 to $10 for booking at ticket offices and airport counters.
6. Don't Pay Too Much for Change Fees
If there's a chance that you'll need to change your flight, book directly with the airline. Orbitz and Travelocity (but not Expedia) charge a $30 fee to change a flight, which is on top of the $100 change fee the airlines assess. Low-cost airlines have much lower change fees. JetBlue charges $20 ($25 on the phone) plus the fare difference, Song charges $25 plus the fare difference, and Southwest has never had a fee—it charges only the difference in fare. But there's some good news from the major airlines: in January, Delta decreased its change fee to $50 from $100. And though the other major airlines hadn't followed suit when this went to press, we expect they will.