Every frequent flier has their bag of tips and tricks for sniffing out the best airfare deals.
And if you count yourselves among the faithfuls of the 'T uesday/Wednesday booking rule' , prepare to have your minds blown.
A Texas A&M University study found airlines are more likely to post discounted airfares on Saturday and Sunday. In fact, rates were about 5 percent cheaper than those booked during the week.
According to the study authors, there's a reason for the discretion: Airlines have figured out that people who browse fares on weekends are more likely traveling for pleasure than business. This is a group that's harder to woo because they have all the time in the world to find the best rate, and airlines post lower fares to reel them in.
"This conjecture is supported by the finding that the weekend purchase effect is distinctly larger on routes with a mixture of both business and leisure customers than on routes that disproportionately serve leisure customers," the authors note.
But don't sleep on the Tuesday/Wednesday rule entirely, says Jeff Klee, CEO of CheapAir.com.
"Day of the week absolutely makes a difference when it comes to what day to fly, with Tuesdays, Wednesdays, and Saturdays usually being the least expensive for trips within the U.S.," he says.
In fact, the discount airfare site just released a study that shows there may be no such thing as a "best day to book" at all. The site's researchers scanned more than 560 million fare search records from 2012 and couldn't come up with a favorite booking day.
" It has become somewhat of an urban legend that it’s cheaper to buy tickets on Tuesdays and Wednesdays," says Klee. "While it’s true that airlines frequently publish system-wide sales on those days, it’s also true that there are large numbers of smaller scale, unpublished sales on other days. Add it all up, and we find that no one day was significantly better than any other."
Here are some other interesting findings from CheapAir.com's data:
How far to book in advance: Seven weeks for domestic flights. Book 11 to 12 weeks out for international flights.
The worst day to buy: Within 11 days of your flight. One day before the flight was the absolute worst.
The best fares for Thanksgiving: For Thanksgiving 2012, the best day to buy was, on average, 96 days (about 14 weeks) before the flight.
The bottom line: Do your homework before booking any flight, and make sure you've got the right tools to set yourself up for the best fares. Many booking sites offer to match fares if you catch them dropping after you've booked your flights. You can also get an excellent idea of when to book domestic fares from Bing.com/travel, which has a 'Buy Indicator' that has yet to fail us. And if you have a destination in mind but have time to find the best fares, sign up for alerts from sites like SmarterTravel.com and Airfarewatchdog.com.
SEE ALSO: 23 secrets to booking cheap airfare >
More From Business Insider