If you’re one of the people planning on making a trip for the holidays this year, you might want to book your flight next week. Research by travel app Hopper concludes that the week of Sept. 13 will offer the lowest holiday travel prices of the season.

That said, expect to pay a bit more than you would have last year. Average U.S. domestic airfare for Thanksgiving will hit $300 this year, Hopper found, a 23% jump from 2020, but still 11% lower than in 2019. Christmas travelers will pay an average of $430, a notable 71% jump from last year—and 10% more than in 2019. (International travelers in late December should expect to pay $969 roundtrip, a 35% increase from last year.)

If next week is a bit too early to book your flight, you’ll definitely want to do so before Halloween. Ticket prices for Thanksgiving soar 40% at the start of November, according to Hopper. (They go up another 25% the week of the holiday.) December travel jumps 18% in the three weeks leading up to Christmas.

For Thanksgiving travel, you’ll save even more if you depart on Monday, Nov. 22. (You’ll actually save even more if you fly on Thanksgiving itself, but that’s a less popular choice.) And avoid flying home on Sunday, Nov. 28. That’s the most expensive day to fly back.

For Christmas travelers, Dec. 21 or Dec. 24 is your best bet for savings. Flying on Dec. 23 will cost an extra 20%. And it’s wise to stay an extra day or two, if you can, as Dec. 26 will be the busiest and most expensive day to return home.

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