Get cheaper air fares depends on not only when you fly, but also when you buy.

On average, the best time to buy a ticket for domestic travel in non-festive seasons in United States is 49 days before departure, based on the study of 560 million records of rates in 2012; for international flights, 81 days is the best time.

Beware of booking tickets much in advance: seats purchased around 200 days are almost as expensive as the discount rates.

Tips for book

Forget the rush. When traveling on dates close to the 4th of July or another festive weekend, you start early–around 10 weeks in advance in the majority of cases, says the Chief Executive of, Jeff Klee. For Thanksgiving, however, might need one month more than that.

Take advantage of the day. Purchase  on Tuesday afternoon, said the Chief Executive of FareCompare, Rick Seaney, since the majority of domestic sales dropped the Monday night are soon equalized by competition.

For the non holiday destinations, buy a weekend; a study from the University of Texas A & M found that strategy results in average savings of 5%.

Check out the numbers. To ensure that your time is appropriate, take advantage of the special functions of the travel search engines. New features driven by fresh data, Price Trend of and Price Predictor of, predict if rates tend upwards or downwards.