Why Sundays and Fridays will be particularly important travel days in 2018

Sunday is the best day to find travel deals, a new Expedia report states. Getty Images

Here’s a general rule of thumb for booking air travel in 2018: To score the best international economy fares, clear out your Sunday and book your departure flight for Friday.

And whatever you do, avoid making any kind of reservations on Friday.

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That’s the latest advice from a major report released jointly by Expedia and the Airlines Reporting Corporation (ARC), which combed through flight data spanning Sept. 1, 2016 to Aug. 31, 2017 to identify patterns on the best times to book air travel, and best times to fly in 2018.

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With a few exceptions, the numbers show that Sunday is the best day of the week to sit down at your laptop or scroll through your smartphone to find the best flight deals. This is true of most countries around the world with the exception of travellers departing from Australia, Iceland, Kuwait, Sri Lanka, Peru, Singapore, Thailand and Tunisia.

Overall, the same is true for booking domestic flights.

The finding, once again, debunks the widely circulated claim that Tuesday is the best day of the week to book.

Meanwhile, for added savings, the second part of the booking formula dictates that for international economy flights, the best day to start your journey is a Thursday or Friday, with the exception of flights departing from Fiji or Saudi Arabia.

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By contrast, Friday is the worst day in general to book your flight, as the average ticket prices are most expensive.

The report also offers advice on the cheapest months to fly for international travel.

For example, travellers who are planning a trip to Hong Kong, Malaysia or Singapore in 2018 will see the biggest savings if they travel in the month of March, while November is the cheapest month to travel to Thailand and South Korea.

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Travel to Japan is forecasted to be cheapest in January, while travel to China is predicted to be cheapest in December.

The cheapest month to embark on an international flight for travellers in Canada and the U.S., meanwhile, is February.

For Europe, the cheapest months for international travel in general are March, May and September.

And the magic month for international travel to Australia and New Zealand? March.