It means that booking around three months in advance could save you £107 for international flights. For example, when flights to Costa Rica were booked two weeks or less before departure, the average ticket price was £843, compared to £1,074 when booked one to two months before travel. That’s a saving of £231. While, if like pretty much everyone, you have your sights set on the Maldives, booking three months ahead rather than a month or less could save you a whopping £853.