A DC voltage switch for high-voltage on-board electrical systems having a housing, at least two stationary contacts, and a moving contact, wherein, in each case, a first contact region of the stationary contacts is routed out of the housing and, in each case, a second contact region of the stationary contacts is arranged in a switching chamber of the housing with the moving contact, wherein the housing is hermetically encapsulated, wherein a cooling chamber which is separated from the switching chamber by a partition wall is arranged above the switching chamber, wherein the partition wall has at least one outlet opening and at least one inlet opening.