Most weeks of the year, Fridays are the busiest days to fly, and Tuesdays are the least busy. But during the holidays, that trend doesn't necessarily hold true.

In most years, the Sunday after Thanksgiving is actually the busiest travel day for U.S. airports, according to the Transportation Security Administration, which tracks the numbers of passengers screened daily. Two days before Christmas and one day before Thanksgiving also tend to draw big airport crowds.

Here's a breakdown of the best and worst days to fly during the winter holidays, and how you can strategize schedules to avoid crowds and save money.

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The Sunday after Thanksgiving is brutal for airport crowds. For every 100 people who flew on Thanksgiving Day 2021, there were 177 people flying out on the Sunday after, according to TSA.

That same Sunday was the year's single busiest airport travel day in both 2019 and 2021 . In 2020, the busiest days were largely concentrated in January and February, before the widespread impact of COVID-19, which would reduce holiday travel later in the year.

Here's a look at the days surrounding Thanksgiving week over the past three years, ranked in order of most to fewest air travelers at the TSA's U.S. checkpoints:

— Sunday after Thanksgiving (most crowded).

— Wednesday before.

— Saturday after.

— Friday before.

— Monday after (Cyber Monday).

— Sunday before.

— Tuesday before.

— Monday before.

— Saturday before.

— Tuesday after (Giving Tuesday).

— Friday after (Black Friday).

— Wednesday after.

— Thanksgiving Day (least crowded).

Assuming past trends continue in 2022, expect Sunday, Nov. 27, to be the busiest travel day around Thanksgiving, followed by Wednesday, Nov. 23. Even if you fly out one day ahead of the biggest crowds, Saturday, Nov. 26, will also likely be busy.

And this year, crowds will likely be bigger than they were over the past couple of years.

"Thanksgiving travel volumes are looking similar to what we typically saw pre-pandemic in 2019," says Hayley Berg, lead economist at travel booking app Hopper.

Christmas airport crowds can be trickier to predict than Thanksgiving crowds given that the holiday falls on a different weekday each year and that air travel patterns are often dictated by the workweek.

But just as the Sunday after Thanksgiving tends to draw huge crowds, the days just after Christmas are wildly popular. And much like how few people travel on Thanksgiving Day itself, relatively few people travel on Christmas Day or New Year's Day.

Here's a look at Christmas and the seven calendar dates before and after over the past three years, ranked by most to fewest average air travelers, based on TSA checkpoint data:

— Dec. 27 (most crowded).

— Dec. 23.

— Dec. 20.

— Dec. 26.

— Dec. 30.

— Dec. 19.

— Dec. 29.

— Dec. 22.

— Dec 28.

— Dec 21.

— Dec. 18.

— Jan. 1 (New Year's Day).

— Dec. 24 (Christmas Eve).

— Dec. 31 (New Year's Eve).

— Dec. 25 (Christmas Day) (least crowded).

The 2022 holiday travel season will be different because Hanukkah, which begins on the 25th of Kislev in the Hebrew calendar , aligns closely with Christmas. While the eight -day celebration sometimes happens in November or early December, it begins this year on Dec. 18 and runs through Dec. 26.

There's also the weeklong celebration of Kwanzaa, which runs from Dec. 26 through Jan. 1. Thus, travelers during that period might be celebrating more than just Christmas, potentially concentrating more holiday crowds in airports than in other years.

What's more is that one of the busiest travel days of the year, Dec. 23 — the day before Christmas Eve — happens to fall on a Friday this year. Friday, you'll recall, is typically the busiest travel day in any given week. Dec. 23 is not an official holiday, but many holiday travelers may leave on that day.

Traveling on the holiday itself is often the best way to avoid crowds. Catch the first flight out for the day, and you might arrive in time for evening festivities. Taking early flights is also considered good practice to reduce your odds of a flight delay. In the first eight months of 2022, 7.3% of flights were delayed because an aircraft arrived late, according to Bureau of Transportation Statistics data .

If you can take the days off work or work remotely, then it can make sense to fly as long before or after a holiday as possible.

Travelers can save an average of 15% by departing the first half of the week instead of the Thursday or Friday before Christmas this year, according to flight data from travel search engine Expedia. Average ticket prices for departures on the Monday before Thanksgiving are 15% cheaper than Wednesday departures, Expedia also found.

Or consider celebrating something like an un-Thanksgiving, where you shift the family dinner by a couple of days or weeks. Turkey, potatoes and pumpkin pie don't need to be reserved for the fourth Thursday of November.