The 4 Days in December You Should Never Fly

Last December, more than 5 million people passed through Canada’s major airports, according to data from the Canadian Air Transport Security Authority (CATSA).

If you were among them, or if you’ve flown in December in years past, you’ve probably accepted that pricey tickets, crowds and stress are just part of the holiday travel deal. But that’s not necessarily true.

While December is indeed a busy month at airports, some days are markedly busier than others. And since being busier often correlates to higher prices (good old supply and demand in action), it stands to reason you might want to avoid those days in particular.

But what days are they? NerdWallet analyzed passenger screening data from CATSA, comparing numbers year over year. Four dates stood out — and they might not be the ones you’d expect.

The worst days to fly in December

By looking at CATSA’s data for Canada’s eight largest airports from 2019 to 2023, we were able to find each year’s five busiest days in December (i.e., most passengers screened). We then identified any of those busy days that occurred across three or more years.

Next, we followed the same process but for Canada’s 17 largest airports, which included the top eight, as well as the next nine biggest.

Whether looking at the smaller pool of eight major airports or the larger pool of 17, the dates are nearly identical. The worst days to travel historically are Dec. 15, 16, 17 and 21.

The worst days to travel historically are Dec. 15, 16, 17 and 21.

Interestingly, if we look at only the last two years, 2022 and 2023, and isolate for the busiest travel days shared by both years, a slightly different set of dates emerges: Dec. 21, 25 and 27.

This could indicate that post-pandemic holiday travel trends are shifting slightly, with more people postponing their travel until closer to the big day — or on the big day itself.

When to travel instead

If you’re flying during the holidays and want to avoid busy, potentially expensive and stressful days, the data is clear: skip Dec. 15-17 and 21.

To figure out when you should fly instead, NerdWallet again analyzed CATSA screened passenger data for the years 2019 through 2023. However, this time we sought out the five days in December with the fewest passengers and identified low travel days shared by at least three years.

Best days to travel in December in Canada:

Dec. 2, 4, 5, 6.

Of course, this information isn’t surprising, considering the winter holiday season often hasn’t started in the first week of December. This year, the season kicks off with the first night of Hanukkah on Dec. 7 and runs through New Year’s Day 2024, which is also the final day of Kwanzaa. In between is Christmas Eve (Dec. 24), Christmas Day (Dec. 25), Boxing Day (Dec. 26) and New Year’s Eve (Dec. 31).

Knowing most people can’t take a month off of work to travel, say, Dec. 6 through Jan. 6, 2025 just to avoid some busy days, we changed our approach. We looked across the years to identify the five days after December 14th that, while not the best possible, have tended to be less busy. Regardless of whether we looked at the top eight airports or expanded to 17, the best days to fly were the same.

The next best days to travel in December:

Dec. 23 and 29.

🤓 Nerdy Tip: To err on the side of caution, you may want to avoid flying Dec. 29 because it falls on Sunday, and Sunday is typically a busier and pricier day to fly.

More things to consider when booking your holiday flights

Here are some additional things to keep in mind as you plan this and any future holiday travel:

If you spend the holidays in a different country, keep in mind regionality. Boxing Day isn’t observed in the U.S., for instance. Ethiopia observes Christmas on Jan. 7 each year, and Chinese New Year can fall somewhere in January or February depending on the year. Be sure to do a little research before booking any travel.
Don’t be afraid to fly the day of a holiday if it works best for you. These dates can sometimes be cheaper since most people want to arrive at their destination in the days preceding.
Realize a good or bad travel day last year might not be the same this year, especially because some holidays, like Hanukkah, change dates annually.
Know that prices will always vary depending on your departure and arrival cities, number of connections, seat class, airport, airline and more. Always shop around to find the best price irrespective of which days have historically been most or least busy.
Use these tips to keep holiday flight costs down and maximize your travel savings.