|• Total||3,486.4 km2 (1,346.1 sq mi)|
|• Land||1,475.28 km2 (569.61 sq mi)|
|• Water||2,011.12 km2 (776.50 sq mi)|
|Area as of 1 January 2014.|
(31 December 2018)
|• Density||6.3/km2 (16/sq mi)|
|Time zone||UTC+1 (CET)|
|• Summer (DST)||UTC+2 (CEST)|
|ISO 3166 code||SE|
The present municipality was created during the local government reform in the late sixties and early seventies. Already in 1967 the City of Öregrund joined the City of Östhammar in a common municipality. It was the first time a former city joined another local government unit. By 1971 the new combined city became a municipality of unitary type and in 1974 more units were added.
All towns with over 200 inhabitants in 2000, from Statistics Sweden.
- Östhammar (seat)
- Skoby (part of this bimunicipal  locality is in Uppsala Municipality)
- "Statistiska centralbyrån, Kommunarealer den 1 januari 2014" (in Swedish). Statistics Sweden. 2014-01-01. Archived from the original (Microsoft Excel) on 2016-09-27. Retrieved 2014-04-18.
- "Folkmängd i riket, län och kommuner 31 december 2018" (in Swedish). Statistics Sweden. February 21, 2019. Retrieved February 23, 2019.
- Östhammar Municipality - Official site