Zizoo has brought its total investment to date to over $10 million following the addition of a Series A round led by Revo Capital.
The Germany-based company's new round of $7.4 million also saw participation from new backers Coparion, Check24 Ventures and Push Ventures.
The company was formed in 2014 as a mechanism for charter providers to connect online with travelers seeking bespoke boat-based trips.
It currently works with 1,500 charter companies in 30 countries worldwide.
Previous investors Axel Springer Digital Ventures, Russmedia International, Founders Fund and MairDumont Ventures also took part in the Series A round.
Zizoo plans to add 40 more employees to its current headcount of 60 with the latest funding, alongside expanding into new markets around the world.
Generation of seafarers
The company believes its core audience is growing due to a concerted uptick in interest from Millennials, claiming boat holidays are the "next big thing in travel".
Some 85% of its customers are first-time trippers and the majority are between 20 and 40-years-old, the company says.
CEO Anna Banicevic says: "With millions of annual website visits and fantastic venue growth rates, we will continue to empower yacht charter companies to meet the massive market represented in millennials."
Revo Capital managing director, Cenk Bayrakdar believes the market is one of the most "under-served verticals" in the industry, despite the "huge potential".
The company last raised a venture round of €1.7 million in July 2016.