Dagebüll is a municipality situated on the west coast of Schleswig-Holstein in the Nordfriesland district of Germany. The modern boundaries of the town were established in 1978 through the merger of three former municipalities: Fahretoft, Juliane-Marien-Koog, and Waygaard.
Historically, Dagebüll was a Hallig, with its earliest houses constructed on artificial dwelling hills that remain visible in certain areas today. The region was eventually secured by sea dikes in 1704.