[Rick Seaney is the CEO and co-founder of FareCompare, and a columnist for Investopedia. The views expressed by columnists are those of the author and do not necessarily reflect the views of Investopedia.]

While the airline industry experienced drastically curtailed airline travel in 2020, analysts are expecting air travel to continue to be robust in 2021 as the economy expands. If you’d like to save money on flights, this will help: a list of days to avoid and days to fly. The information was gleaned from my analysis of literally millions of different flights around the globe, including every departure and destination city in the world. The result is "average cheapest fares" per day, which I used to create the following Do Not Fly calendar for those who want to save.

Note how you probably won't pay a premium for weekend flights in the dead of winter, but they start getting more expensive as early as March. Starting in May, Thursdays and Fridays will also cost you more.

Key Takeaways

  • Flying during peak season can mean expensive airline tickets and jam-packed flights.
  • January and February are usually good times to fly, with the exception of New Year's Day weekend and Feb. 14 thru 17.
  • Weekend flights are generally higher-cost than mid-week or Sundays throughout much of the year.
  • Stay-home dates for saving money are June 22 to Aug. 24, unless you can fly weekdays.

Dates to Avoid in Winter

January: No dates to avoid after Jan. 2 (final day of expensive holiday fares), but note that Jan. 22-30 is an especially cheap time to fly in the U.S. In fact, late January in general is bargain season in much of the world.

February: Again, no particular dates to avoid, but if you are planning a vacation, the latter part of the month is generally a little cheaper. On the other hand, flying around Valentine’s Day (Feb. 14) often means higher ticket prices.

March: Start avoiding weekend travel because fares start rising by more than a third over Tuesday or Wednesday fares.

Dates to Avoid in Spring

April: Avoid weekend flights, which now cost as much as 40% over weekdays.

May: Fares in general continue to creep up, and prices in late May jump for Thursday and Friday flights.

Early June: Avoid flying June 13 and beyond; this marks the start of the pricey pre-summer season.

Dates to Avoid in Summer

Late June: Avoid flying June 22 or beyond; this is the start of peak summer season and fares will be expensive.

July: If possible, avoid the entire month, but we understand this may be impossible. Keep reading for "When You Can’t Avoid Expensive Days," below.

August: Avoid travel through Aug. 24; after that, fares begin to drop for the cheaper fall season.

Dates to Avoid in Fall and Winter

At this point, we don’t provide specific dates because airlines generally do not actively manage prices beyond nine months in the future. You can still book travel beyond this point today, but you will likely pay a mid-range fare that’s higher than if you’d waited.

How long should you wait to shop?

  • About three months in advance of departure for domestic fares
  • About five months ahead for transatlantic travel

That said, you don’t need a crystal ball to know the days immediately surrounding Thanksgiving (Nov. 25) will be expensive, and ditto for Christmas (Dec. 25) and New Year’s (Jan. 1). 

Dates to Avoid for Europe

Europe typically has special dates of its own. Be aware of these.

March 20: Fares rise sharply for spring; if you can fly earlier, do so.

May 22: Spring fares give way to more expensive pre-summer prices.

Late June: Summer peak season pricing gets underway. The good news is, fares actually dip a bit in July and even cheaper fall fares begin in late August or September, depending on the route. Prices should really start to tumble after Sept. 11 this year.

When You Can’t Avoid Expensive Days

We know that sometimes you can't plan according to price. But there still are three steps to take to cut costs.

Always compare airfare prices. If you only check one or two carrier’s fares, you could pay way too much.

Fly midweek. You can almost always save some money by flying on days in the middle of the week—Tuesday, Wednesday—compared to Fridays and Sundays. Saturday is often cheap too.

Look for cheaper destinations. Two things to try: Flights between major airports that are about 90 minutes or shorter are less affected by sharp seasonal price swings. In addition, check out a deal-finding tool on an airfare search site and you will see what’s cheap from your town around the U.S. and around the world.

Here’s hoping you have many safe, wonderful, and inexpensive travels throughout 2021!