If you’re planning a vacation that involves flying, it’s important to know that ticket prices change frequently. If you want to find the best deal possible, remember to do your research and be patient. Regardless of the destination, the Skyscanner and CheapAir websites seem to find the greatest deals. Here are the best times for booking flights, according to your individual needs.

General guidelines

Not everyone can choose the best times and places for vacations because of obligations in the rest of their lives, such as work or family responsibilities. However, if you can reserve a flight between 21 and 121 days within the date of departure, you’re likely to pay within 5 percent of the lowest possible fares. At the least, try to book between 7 to 14 days before the flight. While you might miss out on seat selection, prices will still be incredibly reasonable. Booking less than one week in advance is not recommended because it can cost at least $200 more.

Seasonal vacations

Overall, the best time for booking summer tickets is around 50 days in advance. Since prices drop at the end of the summer travel season, buying at the end of August for a fall or winter vacation saves you money. Overall, August 23 is the best day for buying a ticket.

The best time for buying fall travel tickets is 69 days in advance. If you want a good deal for a winter vacation, buy 62 days ahead of time. These calculations do not include the holiday season, which often hikes prices and leads to more expensive tickets. Spring travel tickets have the best deals three months in advance.

Holidays

If you have plans for Christmas or the New Year celebrations, buy your tickets October 22 and October 29, respectively. These dates translate to an 11-week window before your flight. If you want to travel for Thanksgiving, check holiday trend reports from a site like CheapAir.

Flexible dates

To accommodate flexible travel plans, use Skyscanner, Kayak, or Google Flights. These websites let you search by location or date only via the everywhere or anywhere functions. If you have a particular destination in mind, all three of these sites let you find the most inexpensive times. They can also set price alerts and allow for airport searches.

Don’t underestimate social media when planning vacations. Many airlines have accounts that they use for last-minute flash sales. If you already know where you want to go, research airlines that use the airports to find out when you can get the best deals.