It's the best time of year to book a holiday trip abroad — save big on these flights

Lisbon, Portugal

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If you're planning on spending the winter holidays in Europe or Asia, now is the best time to book your flight.

By booking before July 29, travelers can score the best deals to some of the most popular destinations, according to travel site Kayak.

The site looked at median airfares of search dates from Jan. 1 through Dec. 14, 2018, and travel dates for Dec.15 through Dec. 30 of the same year to determine how travelers can save the most.

"Booking in the summer can save you some major dollars," said Steve Sintra, regional director of North America for Kayak.

Sintra said that most travelers tend to wait to book their flights. Kayak logs three times more searches for holiday trips in October as in July.

Affordable destinations

Paris, France

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If you're planning ahead for the holidays, Lisbon is the city to consider. Travelers can save 50% on a flight to the coastal capital of Portugal by booking before July 29.

Kayak also found travelers can save from 20% to 40% on flights to Amsterdam, Barcelona, Dublin, Milan, London and Reykjavik by booking their flights now.

If you're flying to Paris, Rome or Frankfurt, you still have some time before snagging the best deals. According to Kayak, you can save up to 40% on your flights to those destinations if you book during the first two weeks of September.

Looking for a trip to Asia instead? Kayak found that summer is the best time of year to score some deals there, as well.

Booking before July 29 can save you up to 30% on median airfare on trips to Bangkok, Bali and Ho Chi Minh City, and hitting "buy" on your tickets to Beijing between July 29 and Aug. 5 could save you about 30%.

Other ways to stretch your savings

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Knowing when to book is only one way to save on travel. Here are a few other practical tips that can help you pocket a few bucks.

Buy on the right day. Tuesdays, Wednesdays and Thursdays are the best days of the week to snap up your tickets, according to Liana Corwin, consumer travel expert at Hopper.

Use your travel points and frequent flyer miles. "People leave a lot of points and money on the table because they've never used them before," Corwin said.

Depending on the program, you may be able to share points with family. But watch out for transfer fees, Corwin said.

If your points expire, it might be less expensive to buy them back than to pay for a flight without them, she said.

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Ask about travel insurance. Travel insurance, which can run from 4% to 10% of a trip's total cost, reimburses you in the event of an unexpected cancellation. Make sure you read the fine print, however. The exclusions section of your policy will break down what isn't covered.

Look into the rules of canceling a flight under the travel insurance policy when you are booking with flight points. Sometimes you may be able to buy back the points at a lower cost, and other times you may lose them, said Corwin.

Your credit card may also offer you some travel protections that are similar to what you'd get with travel insurance.

Find the best ticket for your trip. "If folks haven't been traveling that often, they might not realize what each fare actually includes," Corwin said.

Basic economy tickets might require you to pay to choose your seat, check your bags and bring a carry-on, depending on the airline.

If you're flying for Thanksgiving and can pack light, it might make sense to fly basic economy, said Corwin. But you might want to upgrade for Christmas travel if you're bringing gifts.

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