The research has been revealed by travel search engine Kayak.co.uk in its Flight Price Index for the third quarter of 2016.
This sizeable decrease was in comparison to quarter three of last year.
For the top 50 destinations, flight prices fell an average of 15 per cent.
Some areas noted much bigger drops in prices of fares, including the trip from the UK to Dublin.
It fell by 43 per cent from £84 to £48.
The cost of a flight from the UK to Milan saw an even bigger decrease of 46 per cent, from £164 to £88.
Czech’s beautiful capital Prague dropped by 36 per cent from £158 to £100.
Only two destinations out of the entire top 50 saw the average flight price rise.
Japan’s Tokyo was up eight per cent while Marrakesh in Morocco rose by just two per cent.
Venice remained the exact same as its cost last year.
Apart from the average decrease in the cost of flight fares for Brits, other key travel trends were unravelled.
It appears people in the UK aren’t as eager to visit the USA as they once were.
Flight searches for the quarter were down by up to 27 per cent for American destinations.
Despite this, the most searched for flight was to New York, with an average price of £463.
Amsterdam has soared upwards on the preference list for Britons.
The Netherlands capital has seen an increase in searches of 44 per cent, making it the second most popular destination.
Copenhagen showed the most overall progress, rising 19 places in the top destination list to 23rd most popular.
Travel expert at KAYAK Suzanne Perry commented: “The results of our quarterly flight price index for the past three months underlines what we have observed in the past, that flight prices from the UK are continuing to fall.
“The standout trend, however, has been the across-the-board decrease in the popularity of destinations in the US – where searches are mainly down on double digits for flights when compared to the same time last year for nearly all destinations.
“It is likely that this is related to Brexit and the pound weakening significantly against the dollar over the past few months. A holiday to the US has never been the most affordable, and the change in exchange rate means it may have fallen beyond the reach of many Brits this summer.
“Many people may also have been put off visiting the US due to the furore over the presidential election. It’s also possible that this is related to the growing trend amongst Brits of taking more frequent, shorter holidays.”