Any frequent traveller knows booking an airline ticket at the right moment can save a lot of money that can be used on accommodation, food and other trip necessities – but what is the best time to book?

What's the best time to book a flight? All travellers want to know.

What’s the best time to book a flight? All travellers want to know. Image by Yogesh Mhatre / CC BY 2.0

A variety of theories have been posited recently – such as 53 days or 74 days in advance – and now CheapAir.com has weighed in on the debate. The flight booking and comparison site analysed about 1.3 billion air fares as part of an annual study. In a blog post on their findings, the writers conclude that 54 days, on average, was the best number of days in advance to book a flight for travel within the US in 2015.

But, the authors note that is a bit more complicated than just waiting for the 54-day mark as all trips are different and fares fluctuate differently. They looked at three million different trips – booking from one place to another on a specific date – and found that fares were generally best 54 days before, but 53, 52, 45 or 60 days were all optimal dates for almost the same number of flights.

While that may not help anyone looking for a magic number, the writers do note a general pattern of how fares change: “ typically starting off high, slowly coming down, and then a few weeks before flight time starting to climb, with a particularly sharp increase once you’re inside 14 days”.

Its bad news for procrastinators, as the writers dub the period between zero and 13 days before a flight as the “Hail Mary” zone, noting that while there are many stories of huge last-minute savings – the data says it’s unlikely. But CheapAir’s findings are similar to that of Momondo, the British travel comparison site, which found that the best time to buy a ticket is 53 days in advance, which would yield an average savings of about 26%.

Momondo also found that the best time to actually take that flight for savings is on a Tuesday evening, with Saturday’s averaging 11.5% more than earlier in the week. The stats found between 6pm and midnight had cheaper fares.

Read more: Want a cheap flight? – then book 53 days in advance says new study

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