The North Sea Cup is an open chess tournament played in Esbjerg, Denmark. Until 2003 there was an amateur section (a Swiss system tournament) and a 10-player round-robin tournament for titled players. The exceptions are 1986 and 1987. In 1986 the titled section was the play off for the Danish Chess Championship. In 1987 the titled section was replaced by the Danish Juniors' Championship. From 2004 the tournament has only one division, a nine- or ten-round Swiss system.