Exclusive: Expedia's 8 data-driven tips for booking cheaper flights (including best day)

There may be no such thing as a travel hack, but that doesn't mean there's no strategy for saving and optimizing your flights.

A new report from Expedia and the Airlines Reporting Corp. (ARC) analyzes historical booking and pricing trends to debunk some common myths about airline tickets. It offers insights into the best strategies for booking your trips.

“ARC’s data provided valuable insights into debunking travel myths for Expedia’s 2025 Air Hacks Report that will go a long way to helping travelers prepare for their 2025 vacations,” Chuck Thackston, managing director of data science and research at ARC, said in a statement. “In 2025, affordable premium and economy fares can help U.S. passengers as they continue to prioritize international travel with their discretionary spending to explore new destinations around the world.”

Here's what Expedia and ARC found about eight common flight myths:

1. Summer is the most expensive time to travel

It turns out August is the cheapest month to travel, with many kids already returning to school. February and March are actually the most expensive times to fly. Travelers can save up to 12% on domestic flights and up to 7% on international flights by taking a trip in August instead of February.

2. There’s no best day of the week to book flights

It's the myth that everyone has an opinion about, and while there are many skeptics, the data shows that Sunday is actually the best day to book. According to Expedia and ARC, airfares are typically 6% lower for domestic flights and 17% lower for international flights when booked on Sundays compared to Mondays or Fridays.

3. Departure day has no bearing on the cost of a flight

"It's not just when you book, it's when you fly," the report said. Flight prices for Thursday international departures and Saturday domestic departures are typically lower than other days of the week, regardless of destination or class of travel.

4. The further ahead you book, the cheaper it will be

The best booking window just keeps getting closer to the departure date. Booking one to three months ahead for a domestic flight could yield up to 25% savings compared to last-minute bookings. For international flights, the potential savings are even higher. Just 18 to 29 days before departure is when the lowest fares are often posted.

But, Expedia's experts warn, it's a high-risk, high-reward strategy. On popular routes or during peak travel times, your preferred flights could be sold out, and fares could surge if you wait too long.

5. Airfare goes up every year

Tickets were slightly cheaper in 2024 than they were in 2023. On average, domestic economy ticket prices were 1% lower, and international economy tickets were 4% less expensive year-over-year.

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6. Premium tickets are too expensive

Airlines are getting smarter about pricing their premium cabins, and more people are buying them than ever. According to Expedia and ARC's report, the price difference between an economy and a premium cabin ticket is 10% smaller now than it was in 2019.

7. Flights are always full

Sure, if you only travel during peak times. If you can get away in less busy seasons, you may snag that empty adjacent seat.

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8. Cancellations and delays can't be avoided

While it's true that flight delays and cancellations are largely out of a passenger's control, booking smart can decrease the risk of running into those snags. Morning flights are much less likely to be canceled because cancellations typically snowball as the day goes on.

These tips are all based on general trends, but Expedia and other platforms also have tools to help guarantee the best flight deals.

“It’s smart to keep the 2025 Air Hacks in mind when booking flights, but the best hack is to let technology find the best value. Set up Price Alerts, rely on Price Drop Protection to swoop in and reimburse you if prices drop, and use Expedia’s new Flight Deals tool to see where you can fly for at least 20% lower than typical,” Melanie Fish, head of Expedia Group Brands public relations, said in a statement.

Zach Wichter is a travel reporter and writes the Cruising Altitude column for USA TODAY. He is based in New York and you can reach him at zwichter@usatoday.com.

This article originally appeared on USA TODAY: What day is the cheapest to book a flight? 8 myths debunked by Expedia