Accidental pollution at sea can be reduced but never completely eliminated; however, deliberate illegal discharges from ships can indeed be reduced by the strict enforcement of existing regulations and the control, monitoring and surveillance of maritime traffic. Despite this, operational oil discharges are common and represent the main source of marine pollution from ships. To analyse this problem, the Joint Research Centre (JRC) of the European Commission has focused its attention on the need to monitor in the long term sea‐based oil pollution. This research aims, in particular, to map the oil spills, to identify the hot spots and to define the trends in all European seas. For this reason, JRC has collected all relevant data concerning sea‐based oil pollution from different actors and archives. For the North and Baltic seas, data from aerial surveillance were used and, for this reason, all oil spills are real and confirmed. Conversely, the data for the Mediterranean and the Black Sea derive from oil spills detected by JRC in low resolution SAR (Synthertic Aperture Radar) satellite images from archives. For the Mediterranean and the Black Sea, these data represent the only source to draw some preliminary conclusions on marine oil pollution. This paper presents for the first time a comprehensive view of the long term monitoring of sea‐based oil pollution in all the seas around Europe. The key conclusion of this study is that, if the data analysed are not homogenous, operational pollution in the seas around Europe seems to be slightly decreasing.