Airfare can vary dramatically by season, month, week and even day of the week, making it difficult to pinpoint when to book to get the cheapest airfare. A new study by Upgraded Points identifies which days of the week you should buy your flights to get the best price. Not only that, data reveals that individual airlines follow a pattern too, with different airlines offering cheaper fares on different days. The more informed you are, the better chance you have to snag a great deal, so heres what you need to know about which days to book to get the cheapest flights.

　　Upgraded Points gathered fare info from Google Flights for 10 of the busiest domestic flight routesmore than 44,000 flightsover the course of 4 weeks to determine price fluctuations. Southwest Airlines was not included in the study, as the airline does not publish flight data to Google Flights.

　　This analysis reveals that across all airlines, booking on a Monday or Tuesday results in the cheapest fares, an average of 5.2 percent less than the average fare. If you book on a Saturday, youll find that fares are on average 7.3 percent higher.

　　As for specific airlines, American Airlines has the most consistent fares throughout the week, with Thursdays and Fridays coming in slightly cheaper. Delta Air Lines offers their cheapest fares on Thursdays, with an average of $35 in savings. Mondays and Tuesdays tend to be the cheapest days to book for JetBlue and Spirit.

　　"While the flight prices weve explored change day by day, one thing remains constant: the importance of informed decision-making in travel booking. As prices continue to rise, savvy travelers will be looking to save where they can," Upgraded Points Founder and CEO Alex Miller said in the report.

　　For more details on the best times of the week to book, check out Upgraded Points report here.