Wanna save some money on a flight?
Book it 21 days before your trip.
That’s according to a new study by the travel booking site Kayak.com, which found that domestic airfares drop to their lowest level 21 days before departure.
Over a six-month period, they found the average fare for a domestic flight was $370. But that fare dropped to its lowest level, $342, exactly 21 days before takeoff.
But take this advice with a grain of salt. The 21-day rule will likely do you more harm than good for the upcoming holiday travel season, when flights sell out weeks in advance.
And a separate study in January found the lowest airfare is actually booked six weeks before departure.
Still, both studies found that airfares begin to skyrocket by 30% or more seven days before departure. So book your flights at LEAST three weeks in advance to get the best deal.