When is the best time to book a vacation trip?

This is the question that plagues many travellers: when is the best time to book flights for the holidays?

One way to ensure you get the best flight deals is to set airfare alerts for the route you want to take, according to Melanie Lieberman, senior global features editor for The Points Guy. These alerts notify you when flights for your route are disrupted; Plus, they can provide perspective on pricing for that route.

“We really want to encourage travelers to be proactive, to understand what’s normal for their itinerary, what’s a bargain, and when things get really expensive,” Lieberman said. She recommended sites, such as Google Flights and Hopper, to monitor general price trends.

When should I book my flight?

Flight alerts aside, the rule of thumb is to book as early as possible. Lieberman noted, however, that booking at least 21 days before your departure date can usually help you avoid the higher prices.

When booking for the vacation, something to consider is booking your flight for the vacation itself. Ticket prices are often lower for these flights, and traveling on these dates can make for a less crowded and smoother travel experience.

Lieberman warns against waiting until the last minute to book a flight, as this could leave you running out of options and having to book a very expensive ticket.