If you want to book a cheap flight ticket, you shouldn't do that on and Friday. The prices are on average about 13 percent higher than on a Sunday. This is the conclusion of a study by The Wall Street Journal. This leading newspaper investigated and compared the prices of different airlines around the world.
The main reason for the price difference is the fact that airline ticket providers know that many people who plan a last-minute weekend trip do so on Friday. Business trips are also often booked on a Friday and business travelers are less price conscious.
The cheapest day to book a ticket is on Sunday and Tuesday otherwise. Wednesday and Thursday are more expensive days to book an airline ticket.
It also appears that if you are going to fly within Europe, it is best to buy a ticket 140 days before departure.