It's fairly well-known that there's a pretty good chance that the person sitting next to you on any flight will have paid a wildly different price for their ticket. However, what's less well known is that the price you pay for your flight can vary by as much as 80%. So it's worth knowing when to book, and when to fly, in order to get the right price.
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When to book
According to a study by KAYAK, the right amount of time to book in advance depends to a large extent on where you are going. For mid-haul flights, the website says, it's best to start your search two months in advance - and leave booking no later than one month before you fly.
The best discount in the study from booking this far in advance was an 80% saving on flights to Faro. Flights to Majorca, meanwhile, were 75% cheaper when booked two months in advance, flights to Tenerife were 66% cheaper, and flights to Rome, were 61% cheaper.
There is the odd exception to this rule. When it comes Reykjavik, for example, five months in advance is the best time to book, which offers savings of up to 61% with an average price of £69.
Again, there are some exceptions. Holidaymakers aiming to visit New Zealand can get the best price if they book a trip to Auckland seven months in advance (saving up to 58%).
The real mid-haul bargain of 2017 is Madrid. KAYAK claims it's the cheapest destination to fly to from the UK - with an average airfare of £66. Meanwhile Marrakech in Morocco (£93 on average), tops the list as the cheapest airfare internationally.
When to fly
Holidaymakers can save even more if they can be flexible about when they fly. On all routes, both long and short haul, flying out in the middle of the week is the cheapest option. The best departure and return days generally fluctuate between Tuesday and Thursday.
Huge savings can be made - for example, flights to Mallorca departing on a Tuesday with return on Tuesday, can be up to 75% cheaper than those booked to depart on a Saturday with return on Wednesday. It is a similar story for Rome, where the savings are up to 72% for departure on Tuesday, returning Thursday, compared to departing and returning on Saturdays.
Suzanne Perry, travel expert at KAYAK, says: "The research shows that generally, those who are happy to leave their bookings until later can secure the best deals. Especially on long haul, most Brits tend to plan their holidays well in advance for peace of mind, so if they still have empty seats left a couple of months beforehand, airlines will often begin reducing prices to make sure they get filled."
However, Perry points out: "There are also some real anomalies with some destinations, so signing up to tools like Price Alerts from KAYAK can really help travellers get the best deal." You can sign up for this months in advance, and receive notifications whenever the price is particularly attractive.
Of course, there's a proviso that always comes with any recommendation to book close to your departure time: if your flight is filled, then you will end up paying more. You may be able to get around this by conducting your hunts in the small hours of the morning. At this point, some of the flights that have been held by tour operators, but not sold, will become available, and you may be able to get a cheaper deal.
There are no guarantees, however, so if you absolutely need to fly on a specific date and time, and cannot risk either missing out on the flight or paying more if the flight fills unexpectedly, then you may be better off buying at the other end of the spectrum - as early as possible after the flights are released. This won't guarantee the cheapest possible flight, but will guarantee you don't pay through the nose, or miss out altogether.