Once you know when to book, the next lever is finding cheap flights by choosing the right day to fly. Move your trip by even 1–2 days, and the price can drop fast.

Christmas Eve and Christmas Day are usually the best bets for lower fares. Most people want to get to their destination before the holiday, so demand falls on both dates.

Dec. 25 is often the quietest day of the year at U.S. airports, and ticket prices tend to match that pattern. On busy holiday routes, early morning and red-eye flights on these days can come in 10% to 20% cheaper than daytime departures.

The weekend before Christmas is usually the most expensive time to fly out. Then, after the holiday, the Saturday after Christmas is often the busiest day to head home.

If you have some wiggle room, a later return can help. Flying back on Jan. 1 or Jan. 2 may cost less, and Jan. 3 through Jan. 6 is often a cheaper stretch for return flights.

Use the dates below to see if shifting your departure or return by a day could lower the fare:

If your dates are flexible, it’s also worth checking Tuesday and Wednesday departures.

If your ideal dates are already priced out, the next step is knowing when to stop waiting.

Once the best booking window passes, prices usually do one thing: go up.

That happens because Christmas travel demand ramps up fast as Dec. 25 gets closer. Within 31 days of the holiday, fares start climbing. And when you’re fewer than 21 days out, you’re often looking at peak fares or even more.

For domestic U.S. Christmas flights, aim to book in the 32–73-day window, ideally by Oct. 31. For international trips from the U.S., book 4–6 months ahead.

For international Christmas travel, it’s smart to book when you spot a fair fare. Late-season prices usually don’t fall.

Use this as your stop-waiting guide:

If that window has already passed, the next move is simple: find cheap flights fast before the cheapest seats disappear.