Small reticulate Nummulites are found across the Eocene shallow marine deposits of the Paris Basin, Belgium, as far north as northern Germany and southern United Kingdom. Only two isolated instances of Nummulites at higher latitudes than this are known, from the Rockall bank and Wyville-Thomson ridge in the north Atlantic, and no Nummulites have been reported from the Nordic North Sea Basin – until now. Here Nummulites planulatus is described within a glacial erratic dredged from Jyske Rev in the Danish North Sea of likely Ypresian age. Whilst the specimen is not in situ, it indicates that populations of Nummulites were living further north in the North Sea region than previously known. This range expansion may have been facilitated by the hyperthermal events of the early Eocene.