Sommelsdijk is a village on the island of Goeree-Overflakkee, South Holland, the Netherlands, and part of the municipality of the same name. Sommelsdijk has 7,383 inhabitants which makes it the largest settlement on the island.
In the past, Sommelsdijk was the only place on the island of Goeree-Overflakee that was part of the province of Zeeland. In 1805 it was made a part of Holland, and remained such under the amendment of the Dutch Constitution of 1814.
Early March 1941 during the Second World War, nearly two hundred young men from Sommelsdijk were incarcerated for one month because of insulting the German army and the Dutch police.
Sommelsdijk was a separate municipality until 1966, when it became part of Middelharnis. Most recently, it was made part of the new municipality of Goeree-Overflakkee in 2013.