Looking for Cheap Holiday Travel? Book Airfare Now

By Louis DeNicola, Cheapism.com

Headed home for the holidays or perhaps leaving home to visit family? In either case the question of when to lock in cheap holiday airfare is always a hot topic. There are a number of rules and tips flying around the Internet faster than a Concord: Book on a Tuesday or Wednesday (maybe a good idea). Clear your cookies or search in private browser mode (probably only matters if you're doing a lot of searches in one day). Book X number of days before the flight (is that 7, 14, or 21 days, or more like 6 weeks?).

Related: Best cheap airlines to fly

The problem is, airline ticket prices fluctuate daily and sometimes by the hour. Numerous factors affect airfare and each analyst weighs them differently, which helps explain why a study by Kayak showing 21 days prior to flying is the best time to buy a ticket doesn't match CheapAir.com's conclusion that 49 days is the real number. Both results were announced within months of each other and used millions of data points to arrive at their conclusions. As CheapAir's CEO Jeff Klee stated, some data pointed to 331 days in advance as optimal and some to the day before. So what's a budget-minded traveler to do? Check early and check often, Klee advises, and you'll know a good deal when you see one. This strategy is critical for anyone on the prowl for cheap holiday airfare.

Related: Top travel sites to grab the best deals

The "book as early as possible" camp boasts its share of travel agents. As one explains on a blog, the search technology they use lets them see beyond price to how many seats are available in each booking class. Not strictly business or coach, mind you, but sub-classes that usually have a letter designation indicating the seat price. The blogger notes that the cheapest classes usually sell out first, meaning booking early is advantageous. A post by another travel agent at Reddit likewise urges early action and notes that price fluctuations from day to day could reflect tickets having been placed on hold by customers and subsequently released. Empty seats are costly to the airlines, so as flight day approaches fares may drop to clear out excess supply. Gambling on the sudden appearance of cheap airfare shortly before a planned holiday trip is risky, though. When airlines know they're likely to fill every seat, last-minute buying can mean paying a premium.

Related: Our airline fees comparison analysis

For consumers who think they see a good fare but are unsure whether to snatch it, many airlines allow holds that lock in the price for up to 24 hours. Airfare Watchdog created a chart with a rundown of the airlines' and online travel sites' policies regarding ticket holds. If the airfare drops after the hold period, however, buyers may be out of luck. Airlines don't issue refunds although they generally let customers cancel a flight and rebook. But as outlined in Cheapism's airline fee guide, prices to do so run as high as $200 (at United, Delta, American, and US Airways) but may be as low as $50 to $75; Southwest Airlines doesn't charge anything at all. With some carriers, then, it probably pays to lock in holiday airfare now -- if the ticket price drops by more than the rebooking fee, you'll score a win.

To keep tabs on post-purchase price movements, buy a ticket through Yapta, which monitors prices and alerts flyers if prices fall. CheapAir.com is another route to cheap holiday airfare. This site offers a price-drop payback: If the price falls for an identical itinerary, the site pays you the difference up to $100 in the form of credit towards future purchases.

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