Booking flights on the cheapest day of the week can save up to 13 percent off the cost of flights, research has revealed.

Costs can vary widely due to factors such as demand, the method of and the timing of making the booking.

And research from the Airlines Reporting Corporation (ARC) indicates that Sunday bookings have been cheaper than on other days of the week for five years in a row.

Data from the ARC found that travellers booking on Sunday can save up to 13 percent on domestic and international flights compared to Fridays, which are often the most expensive day to buy.

Mario Van Poppel, CEO of currency exchange firm Manor FX, says: “We all know that the cost of flights fluctuate greatly and it can be difficult to know how and when to search to get the best deal.

“It’s interesting to see that booking on a Sunday may well be better than on other days of the week, and it could reap rewards to reserve flights while winding down for the weekend."

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For tickets to one of the most popular destinations, the cheapest day to fly is an extra special one. 

If you’re wanting to fly to New York, travel experts at Netflights have revealed the best day to fly to fly is Christmas Day itself.

Amanda Parker from Netflights says: “Christmas Day flights are the cheapest New York flights by a mile, you can grab a proper bargain. You might even find that the airport is quieter, so much more relaxing with that pint in your hand. If you go for a morning flight on Christmas Day, you’ll find that the queues are small and you'll get through security a lot quicker, which means less chance of delays."

Some airlines will give you festive treats, meals, or even special services on flights taking off on Christmas Day, which make for a very special flying experience.

Travelers can use additional cost-saving strategies, like pre-booking airport parking to save on fees, or opting for connecting flights, which are often cheaper than direct options.

“There are a range of other ways to save money on trips abroad too, such as booking airport car parking in advance and exchanging your travel money before you go.”

And for getting your hands on travel currencies, it’s generally best to research the best rates and get cash for day-to-day spending before you go. This is because foreign exchange bureaus and ATMs in other countries can leave you exposed to worse rates and fees.