As the holiday season approaches, you may want to think twice before pulling the trigger on booking airfare right away, according to Kayak.

Researchers at the travel search engine combed through 2013 data and compiled tips for three of the biggest travel holidays days of the year.  

It might be expected that booking too late could cost you almost 50 percent more than those who planned ahead. But conventional wisdom about booking early doesn’t necessarily hold true. The website data showed that booking an average of two to three weeks in advance for domestic travel yields optimal savings.

Flying out on the actual holiday—Thanksgiving Day or Christmas Day—can also save big money. And if you’re planning an international vacation around the holiday season, being flexible may mean more money for cocktails on the beach.

Check out Kayak’s holiday travel tips below.

Thanksgiving

- For domestic travel, Kayak recommends booking 2-4 weeks in advance. In 2013, the lowest average fares for domestic travel were found in early November.

-International travelers should book ASAP. Late November saw an increase in fares to Europe, Asia and South America.

-Traveling on Thanksgiving Day can save travelers as much as 30 percent below average fares. Returning on the Monday or Tuesday after the weekend can save you up to 20 percent.

Christmas

-Kayak recommends booking domestic airfare  three weeks before intended travel date. But like Thanksgiving, international travelers should lock in their fares right away.

-Booking too late can cost you big time. Mid December fares skyrocket to as much as 50 percent above the lowest available fares.

New Year’s Eve/New Year’s

-Book New Year’s Eve domestic travel about two weeks from anticipated departure date. Lowest fares for New Year’s holidays were found in early December.

-Flying out on Christmas Day can yield up to 33 percent in savings over average fares. If you can't make that work, the 23rd or the 24th are also pretty good days to fly out.