The firm, which specialises in the short-haul beach market, floated on the London Stock Exchange in September.
Group operating profit for the year ended September 30, rose from £3.8 million to £8 million. Revenues also increased from £45.8 million to £63.1 million.
The firm fell to a pre-tax loss of £2.5 million largely because of a shareholder interest payment of £7.8 million.
Simon Cooper, chief executive, said: "2015 has been a highly successful year for On the Beach, delivering substantial growth and culminating in our IPO in September 2015.
“Our results demonstrate how we are successfully building a leading position as more consumers discover the ease of use and wide choice of beach holidays that our platforms offer."