If you’re wondering which is the best day of the week to book flights, as so many travelers do, you might find yourself reading a lot of tips that say Tuesdays are the unrivaled winner, especially for U.S.-based trips. Why? Because Tuesdays are supposedly when competitive airlines like Southwest and Alaska reassess their fares to match or undercut competitors’ prices—and competitors supposedly follow suit.
But is there any data out there to support that anecdotal travel wisdom? A new study of domestic flight pricing by Qtrip, an online travel agency affiliated with CheapAir, suggests that Tuesdays are good for one thing, but it’s not for booking.
The study is based on extensive mining of actual ticket prices: “The team crunched more than 917 million airfares in 8,000 markets to reveal the best and worst times to book U.S. domestic flights, Qtrip said. “The study finds that airfares have become less volatile over the last few years, and the best deals appear progressively earlier.”
The Best Time to Book a Flight: The Window
One thing proven by this study (and others) is clear: You’ll find the lowest domestic economy fares, on average, if you book in the “Prime Booking Window” of 127 to 21 days before you want to travel. Buying during this period generally gets you a fare within five percent of the very lowest available. Comparisons are based on the average of all airfares sold within each time period.
This is a very wide window—far wider than most “best time to buy” postings that other OTAs often publish. And it tracks with my conclusions in analysis of those earlier reports: Although the very lowest fares may zero in on a single date—Qtrip says 77 days in advance—travelers who book a lot earlier and a bit later usually don’t pay a big premium over the very lowest figure. Seasonally, the best-buy times are 49 days in advance for winter travel, 77 days for fall travel, 85 days for spring, and 113 days for summer. But that overall window is wide regardless of season.
Qtrip lists some further conclusions about the time frame:
- Booking 305 to 202 days in advance guarantees that you’ll pretty much get exactly what you want—flights, seats, and such. But that wide-choice option is likely to add an additional $50 to your fare.
- Booking 201 to 128 days in advance is a good idea if you want to compromise between widest choice and lowest fares. But buying in this period adds $30 to your ticket.
- Waiting until fewer than 21 days are left means you’re gambling on finding a good left-over deal or a flash sale. Waiting has some advantages, especially lowering your risk of facing a stiff ticket change penalty is you have to cancel or change your trip. But unless you luck out with a great flash-sale deal, waiting also means fewer choices and higher prices—as much as $200 a ticket if you wait until less than a full week.
Is There a Best Day of the Week to Book Flights?
Qtrip also found that, contrary to all that “book on Tuesday” wisdom, the day of the week you buy your tickets affects the airfare very little—only by only $1 on average. That’s hardly a “perfect” time.
But the best day and time to travel is a different story. Fares for traveling on Tuesdays, averaging $301, are the lowest. Wednesdays are close, at $304. The most expensive day to fly, by far, is Sunday, at $398.
The fares on the other days range between $340 and $364—probably not enough to entice you into a suboptimal itinerary just to knock a few bucks off the airfare. But this makes it clear that when you’re trying to get the cheapest fare, you want to be thinking about your travel dates, rather than the date you’re hitting “book.” And of course, that will waver depending on the season you’re traveling in: summer and holidays are the most expensive times to fly.
As to the best months to travel, fares are lowest for travel in January, September, and October, at $306 to $320. And the highest airfares hit in March, June, and December, at $370 to $374.
This is one of the most extensive “time to buy” reports we’ve seen in some time, and it reveals some new wisdom about how airfare booking is changing, especially since it notes that deals now come earlier and are “less volatile.” Maybe Tuesdays once were the day to book, but now they’re simply one of the better days to travel.
It will, however, be interesting to see if any later reports support or contradict the Qtrip findings.
Editor’s note: SmarterTravel’s Shannon McMahon contributed to this story.
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More from SmarterTravel:
- When Should You Buy Your Flight?
- The 10 Cheapest Places to Fly Right Now
- 7 Airfare Analysts Weigh in on When to Book a Flight
Consumer advocate Ed Perkins has been writing about travel for more than three decades. The founding editor of the Consumer Reports Travel Letter, he continues to inform travelers and fight consumer abuse every day at SmarterTravel.