Sibolga (formerly sometimes Siboga) is a city and a port located in the natural harbor of Sibolga Bay on the west coast of North Sumatra province, in Indonesia.
It is located on the western side of North Sumatra, facing the Indian Ocean and is a transit harbor to the Nias island which was hard hit during the 2004 Indian Ocean earthquake. Sibolga is also a semi-enclave within Central Tapanuli Regency, as Sibolga borders with Central Tapanuli Regency in the north, east, and south, while it borders with the Mentawai Strait in the west.
The city has an area of 10.77 km2 and had a population of 84,444 at the 2010 census and 89,584 at the 2020 census.