When should you book international airfare?

Only 34 days until liftoff! Photo courtesy of Andreas.

Hey Cheapos: You know the age-old question “when should I book a flight to get the best deal?” Is it better to book many months in advance or at the last minute? What about holidays?

Recently the flight gurus over at Kayak.com looked into the matter. By sifting through a billion (with a “b”) flight searches from January 2011 – December 2011, they were able to draw a few conclusions.

Here’s what they found:

Domestic flights

Booking 21 days prior to departure is approximately 8% cheaper than booking six months in advance.

International flights

Booking 34 days prior to departure is approximately 4% cheaper than booking six months in advance.

Day of week

And don’t forget, according to the experts, Tuesdays and Wednesdays are the best days of the week to snag a deal.

When do you book?

Have you found the same? Tell us about your flight booking habits in the comments section.