Start planning now to save big.

Rockefeller Center Ice Rink
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October is upon us and before you know it, the holiday season will be here. That means it’s time to start booking travel for Christmas, Hanukkah, and New Year’s Eve. Booking site TripAdvisor just announced its “Best Time to Book” holiday report, which details the best time to reserve a hotel for the busy (and expensive) travel season.

If you’re looking to book a hotel for your holiday travels, the month of November is the best time to make reservations. “Travelers researching U.S. hotels for the December holidays can find value throughout the year, but those booking on TripAdvisor in November can find rates that are 20 percent less than the highest annual prices,” Brooke Ferencsik, senior director of communications for TripAdvisor, said in a press release.

TripAdvisor researchers looked at historical hotel bookings and rates (in 2014 and 2015) for stays during the last two weeks of December to find any periods when hotel rates were less than average. After looking at nine popular destinations, they found that the best times to book varied by region and some cities’ hotel rates dramatically fluctuate week to week.

Take a look at the data from TripAdvisor’s report for the best time to book a hotel if you’re visiting these U.S. and world cities:

  • Bangkok: late July to end of year for 13% savings
  • Barcelona: late July to the end of the year for 13% savings
  • Beijing: October to end of the year for 17% savings
  • Berlin: November to end of year for 35% savings
  • Buenos Aires: late December for 14% savings
  • Cancun: late November for 17% savings
  • Cape Town: mid-September to end of year for 14% savings
  • Chicago: October until the end of the year; during Thanksgiving week for 12% savings
  • Dubai: mid-December for 41% savings
  • Dublin: early December for 26% savings
  • Hanoi: prices are under average until mid-November when they rise as much as 17%
  • Istanbul: mid-November for 26% savings
  • Jakarta: late August until end of the year for 29% savings
  • London: mid-November for 20% savings; mid-December for 35% savings
  • Marrakech: late October and late November for 19% savings
  • Moscow: August for 34% savings
  • Mumbai: late August for 17% savings
  • New York City: mid-September and mid-November
  • Orlando: It’s best to book early in the year as prices can dramatically change from week to week; if you’re looking after September, prices are below or at average rates in late October and late November
  • Paris: early November until end of year for 23% savings
  • Rome: November for 20% savings
  • San Francisco: mid September for 24% savings; prices drop again on Thanksgiving week and December
  • Singapore: August until end of the year for 16% savings
  • Sydney: late August until end of the year for 55% savings