Lots of ink and pixels have been devoted to the quest for an answer to the question, "When is the best time to buy airline tickets?" My pat answer has always been, "When they're on sale," but colleague George Hobica of Airfare Watchdog says -- and I agree -- you can't predict the next sale. Nevertheless, folks keep trying, and you might want to check out the possibilities.
The latest information comes from the online travel agency CheapAir.com, focused on how far in advance the optimum time to buy might be. CheapAir's data are based on extensive mining of its own purchase records:
Check the calendar
On historical average, says CheapAir, the ideal time to buy a domestic ticket is 79 days, or seven weeks, in advance of departure, when the average fare for the sample was about $400. The earliest data were for seven months in advance, where the average fare was $475. It decreased slowly and steadily until the 49-day point; after that, it increased slowly until 11 days in advance, when it spiked to more than $600 on the day before the flight.
For international tickets, the "sweet spot" was a little more in advance: 81 days, with good deals available generally 11 to 12 weeks in advance.
CheapAir's findings generally track with others: The Economist reported an "eight-week" rule, and Angie's List cites a report from the Airlines Reporting Corp with six weeks as the optimum.
The report also notes that you find lots of deviations from this average. CheapAir found some routes where the best time to buy was when the flight first opened, 331 days in advance, and others when the cheapest tickets were last-minute. And, of course, you're better off buying earlier for travel around major holidays.
The report's data dispute the urban legend about buying tickets on Tuesday and Wednesday: CheapAir found little day-to-day difference.
Use airfare predictors
Two online outfits -- Bing Travel and most recently Kayak -- boast a different approach: "Buy or wait a week" airfare predictors on their search engines. I'm currently testing them and see how they compare.
Beyond trying to pick the best periods to buy, you have the option of tracking fares and the possibility of getting a refund if a fare drops after you buy. CheapAir has what appears to be one of the best such programs: "Price Drop Payback" promises that if you buy a ticket through CheapAir and the fare subsequently goes down, the agency will issue a credit in the amount of the difference, up to a maximum of $100. The deal applies only to online purchases of nonrefundable economy-class tickets, and only to fare drops posted on CheapAir for the exact same itinerary.
Other big online travel agencies provide somewhat similar programs. Orbitz offers a credit up to 110 percent of the difference, but only if someone else actually books the identical itinerary on Orbitz. Expedia offers a guarantee, but only for price drops that occur within 24 hours of purchase.
Sign up for alerts
Another approach is to request an alert whenever a fare drops on some route you want to fly. Here, you have lots of options: Most big online travel agencies offer such a service, some airlines offer it, and some independent third-party travel information sites, including SmarterTravel.com, the source that posts my columns. Most third-party agencies do not include Allegiant and Southwest, two lines that block "screen scraping" by external agencies, but George Hobica's human-powered AirfareWatchdog.com does cover these lines. You enter one or more routes, and your email address and the source notifies you of a fare drop. These days, some of them also provide smartphone and iPad apps.
All in all, you won't find a single magic bullet answer to the when-to-buy question. Instead, your best protection is to avail yourself of a number of different approaches and keep on top of the airfare marketplace.