Unique Caribbean Holidays Ltd (UCHL) launched to agents on April 10, 2017, with Sandals now reporting more than 30% of all agent bookings since have been made online via the trade booking engine.
The operator said "many agents" had used the platform to book a Sandals or Beaches holiday for their clients for the first time.
Karl Thompson, managing director for UCHL, representing Sandals and Beaches Resorts, said securing the "overwhelming support" of trade and airline partners during what he described as "a tumultuous period for the business" was "a huge success".
"They trusted us to deliver and we did so despite the challenge of launching a brand new booking system alongside a new business.
"Our business from the UK overall has grown, with trade business exceeding our expectations,” he added."
Agents will also soon be able to book twin and multi-centre holidays on the trade website, which Sandals said had been made more user friendly through functionalities such as a flight and price availability calendar, enabling agents to see prices on a monthly view.
Thompson added: "Both of these initiatives have taken a year to develop but will make a huge difference to agents and their ability to convert enquiries, and with the twin centres, secure an increasingly popular choice of holiday.
"We will continue to improve our trade website, giving agents a tool that will increase their productivity with ever-improving efficiency."