When's the best time to book plane tickets to get cheaper flights?

If you’re looking for the best deal on airfare, don’t wait until Tuesday. The idea that cheaper seats can be booked when the clock strikes midnight Monday night is just a myth, according to travel app Hopper.

That advice is a relic of a former time, says Hayley Berg, Hopper’s lead economist. Back before airlines had machine-learning revenue models, employees would clock out on Fridays, flights would sell over the weekend, and they’d come in on Monday morning and adjust prices if routes weren’t selling well. That usually took a bit of time, and flights were cheaper to book on Tuesday once those adjustments had gone through the system.

But this hasn’t been the case in the past 15 years or so, says Berg.


“Now there is so much dynamic pricing happening and so many fare classes that the lowest price available on a particular route can be found 16 different times in the course of a week,” she says. Berg adds that airline pricing is volatile and happens automatically on computer-based models.

To determine if there were any kernels of truth in the Tuesday myth, Berg and the Hopper team looked at every data point for two weeks’ worth of flights along a single route: New York’s JFK to Boston Logan, a popular pairing of business travel hubs served by many major airlines. To do so, she pulled every price offered from the beginning of the year up to the departure dates in September.

Berg found that the lowest fare was actually offered every day of the week and most frequently on Wednesdays and Thursdays overall, showing no benefit to waiting until Tuesday to book a flight.

Busting the Cache-Clearing Myth

Another common legend is that airlines and search engines use cookies to track your shopping activity to keep increasing the price you see rather than “allowing” you to find a deal. Clearing your browser history, believers say, can result in more favorable rates.

“That’s just not true,” says Berg, who insists that airlines aren’t out to get customers. If someone does a search for a flight in the morning and it’s more expensive in the evening when they search again, that’s likely because the fare bucket of lower-priced seats had sold out by then, not because it increased just for them as a direct result of multiple searches.

So, What Works?

So now that the Tuesday myth has been busted once and for all and you can leave your browser cache alone, here are a few things that still do work to lower the cost of those dreadfully expensive airfares—in addition to the old standbys of booking on points and miles and being flexible about a layover.

Pick a midweek departure date (and avoid the weekend)
The good news about Tuesday is that it’s a great day to fly—pricewise at least. Tuesdays and Wednesdays are typically the least expensive days to travel, and you can save about 15% on domestic flights or 8% on international flights if you fly on a Wednesday compared with flying on a Sunday, according to data from Hopper.

Be flexible with travel dates
If you open the calendar view of Google Flights or Hopper, it’s plain to see how shifting your travel dates by one or two days can sometimes save hundreds of dollars. The Sunday after Thanksgiving, for example, is one of the busiest travel days of the year—making it one of the most expensive. Berg says if travelers pick a 6:00 a.m. flight on the Monday after Thanksgiving, they can usually save upwards of $300 compared to a buying the 9:00 p.m. flight the night before. All they have to sacrifice is a little sleep. “Flexibility can completely change your travel budget,” says Berg. “It’s not just $15 here or there.”

The same applies to other holiday weekends. Take Memorial Day in the US, which falls on a Monday: On days like these, it’s advantageous to fly out on Saturday and come back Tuesday, rather than the more common Thursday departure and Monday return. Shifting your vacation this way can cut your ticket price in half, depending on where you’re going and when you’re booking.


For domestic departures, buy your tickets a month ahead of time …
Data from the Expedia Air Travel Hacks Report suggest booking around 28 before departure for domestic flights in the US to save 24% on average compared with last minute booking. But don’t book too early either; airfare is generally more expensive in the 3.5 to 6 months before domestic departures.

… But book summer vacation flights in January
Data from Kayak suggests that January is a great time to book flights and that they are typically lower priced at the start of the year after the holidays. There’s also generally lower demand then, too. And if travelers do want to go to Europe in the peak summer month of August, they can save 20% if they purchase their flights eight months in advance, as opposed to booking last minute.

Flip your usual flight times
According to data from Kayak, if a domestic traveler in the US picks a flight that leaves from 7 p.m. and 10 p.m., they can save 37% versus a flight that leaves in the early morning hours of 4 a.m. and 9 a.m. But there’s a risk in this strategy: Flight delays often stack up as the day progresses, leaving later departures with the greatest odds of a schedule interruption. The opposite is true for international flights, which have savings of up to 13% if travelers book an early-morning takeoff time; these longer-haul overnight flights also tend to get prioritized for on-time departures.

Plan ahead using a price monitoring system
Make technology do the hard work for you—it’s an application of data science that should help make everyone’s life a bit better. There are several trusted options to track fares. Hopper has a very successful price-prediction system—which it even guarantees, on certain routes. Ditto Kayak, with its “ price forecast” and “ Best Time to Travel” tools. Google Flights also has a new cheapest time to book feature that gives data on the best pricing windows for routes. This feature gives users insights on the optimal times to book particular routes based on historical data—it provides insights across the globe, not just for flights originating from the US. Google also offers a price tracking system that automatically notifies users if prices drop (or rise) on their chosen dates, and they can get notifications for good deals that may be worth pouncing on if their dates are flexible.