The maritime boundary between Denmark and the United Kingdom in the North Sea is an equidistance line, defined by only its two terminal points, that spans eleven nautical miles. A tripoint between the United Kingdom, Denmark, and Norway comprises the northern endpoint of the boundary, while a tripoint between the United Kingdom, Denmark, and Germany forms the southern endpoint. The boundary was established through a bilateral agreement in 1966, and later amended in 1971. A 2009 Exchange of Notes established the original continental shelf boundary to apply to the two States’ exclusive economic zones, creating one all-purpose maritime boundary.

Denmark and the United Kingdom also share a maritime boundary in the North Atlantic Ocean: Denmark (Faroe Islands)–United Kingdom.