The European Marine Observation and Data Network (EMODnet) is launching its fully unified marine data service. At its inception, EMODnet was organised into 7 thematic packages: bathymetry, geology, physics, chemistry, biology, seabed habitats and human activities, each with their own portal. From now on, the different thematic portals will be integrated into a single central EMODnet portal providing seamless, open and free access to data and information services with unique new features. The unified EMODnet data service is a game changer for in situ marine data users, allowing seamless cross-border and multi-thematic data extraction at the level required by marine managers and policy makers, the blue economy and private sector, the scientific research community, etc.