Here's exactly how many days before your trip to purchase your flight.
A new study from CheapAir.com has revealed that the best time to buy a domestic plane ticket is, on average, 54 days before the scheduled flight.
The study found that “first dibs” tickets — six to 11 months in advance — tend to be on the higher side, as flights have just opened and airlines are less desperate to make sales. Even “peace of mind” tickets — three and a half to six months in advance — can have moderately pricey fares, though there are typically more affordable fares than first dibs. Three weeks to three and a half months is the “prime booking window.” Any shorter and you’ll “push your luck” (two to three weeks) or risk a “Hail Mary” (zero to two weeks).
“The most important rule is fairly obvious: don’t wait until the last minute, as that rarely works out,” Jeff Klee, CEO of CheapAir, said in a statement. “But beyond that, you also want to be careful not to buy too early. I always suggest that travelers check fares early and often and get familiar with the market. Then, when you see a good deal pop up, grab it, because it likely won’t last very long.”
CheapAir found that the fare for a flight changes an average of 71 times between its opening and the day it takes off. That’s an average price change of every four and half days at a rate of $33 up or down.
To obtain the results of the study, the company said it surveyed data from 921 million airfares from 2.9 million trips.
This story originally appeared on Money.com.