WASHINGTON — At times, it seems like getting the best deal on holiday travel requires a bit of alchemy, especially for those trying to plan ahead.

Though most of us are thinking about Halloween, online travel companies have already started touting their wares for holiday travel.

They say now is the time to book that flight.

Expedia recently released a report on holiday trends addressing travelers’ oft-asked question of “should I wait or buy now?”

According to the report, the lowest ticket prices on most domestic flights tend to pop up between 50 and 100 days prior to departure — the sweet spot for Thanksgiving flights is right about now. These flights cost roughly $85 less than the $496 average.

Expedia’s report drew data from the Airlines Reporting Corp., the International Air Transport Association, Diio Mi, and the Airline Tariff Publishing Company.

According to Orbitz, getting the best price on your flight comes down to these “magic numbers” 6, 9 and 10. The bad news: They’re referring to Tuesday (Oct. 6); Friday (Oct. 9); and Saturday (Oct. 10).

Tuesday is the best day to book Thanksgiving flights; Friday is the best day to book Christmas flights; and Saturday is the best day to book New Year’s Eve flights, Orbitz says.

The travel site — which claimed it “analyzed a huge chunk of Orbitz booking data to determine the best three days to book holiday travel”— didn’t provide specific figures, but stated that fares are 5 percent lower than average on those days.

Overall, holiday flights are projected to be cheaper this year, travel research firm Hopper predicts.

Hopper’s Consumer Airfare Index combined combed through search data in order come up with a real-time estimate of overall airfare prices.

According to its projections, fares for the rest of the year will be 7 percent cheaper than they were in 2014.