Cheap Christmas Airfare: The 10 Best Web Sites

Dec. 1, 2009— -- You are looking to book a vacation but want the cheapest possible airfare . There are countless Web sites out there with airfare searches, but some offer substantially cheaper flights than others. Most travelers will scour several sites before actually booking a ticket.

So we decided to put 10 of our favorite sites to the test. We looked at cost, flight options and ease of use. The idea was to look at five random itineraries and see which site offered the best fares.

The results will surprise you. While some trips were nearly identical across the board, others differed dramatically from site to site.

All searching was done Friday, Oct. 30. The trips selected were: New York to Denver from Nov. 26 to Nov. 29 (nothing like a little Thanksgiving travel, the lessons of which can now be applied to Christmas), Chicago to London from Dec. 14 to Dec. 21, Nashville to Omaha from Dec. 3 to Dec. 10, San Francisco to Houston from Nov. 19 to Nov. 23 and, finally, Minneapolis to Miami from Jan. 10 to Jan. 15.

We should note that none of these sites include Southwest Airlines, which likes to keep its system to itself and not pay out booking referral fees. (For our search, this did not matter because Southwest was not cheaper on any of the routes.)

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This might be one of the big powerhouses of the travel industry, but when looking for airfare, we found the site was clunky and not cheaper than any of the others. Travelocity no longer charges to book flights and, like other sites, guarantees that if you book a vacation package and the fare drops (the exact same flights and hotel on the same dates), you will get that lower price.

The real annoyance here was that Travelocity kept trying to sell us hotel rooms. Also, the price here wasn't extremely clear. The price (with taxes and fees) was listed but not displayed as large as the initial price. Finally, Travelocity automatically clicked the "yes" button next to purchasing additional flight protection for $39.95 a person on our London flight.

Our searches on the site averaged 20 seconds.

For New York to Denver, the cheapest Travelocity fare was $419 with tax, with one stop on United. The cheapest nonstop was $432 on Delta. We eventually found two nonstop flights for $403 on other sites (we'll get to that in a minute) leaving on Delta and returning on Continental.

Chicago to London didn't fare much better. The best Travelocity gave us was a $836 nonstop on American Airlines. Three other sites (Expedia, Fly.com and ITASoftware) gave us $829 nonstop, leaving on United and coming back on BMI. (Hey, it's $7.) Travelocity didn't show the cheaper one-stop connections, including a popular $811 on KLM that several other sites provided and two other options we found on other sites for $805 and $807.