East Sumba Regency

East Sumba Regency
Kabupaten Sumba Timur
Warinding Hill
Location within East Nusa Tenggara
East Sumba Regency
East Sumba Regency
East Sumba Regency (Lesser Sunda Islands)
East Sumba Regency
East Sumba Regency (Indonesia)
Coordinates: 9°53′00″S 120°15′00″E / 9.8833°S 120.2500°E / -9.8833; 120.2500
Country Indonesia
RegionLesser Sunda Islands
ProvinceEast Nusa Tenggara
CapitalWaingapu
Government
 • RegentUmbu Lili Pekuwali
 • Vice RegentYonathan Hani
Area
 • Total
7,000.5 km2 (2,702.9 sq mi)
Population
 (mid 2025 estimate)
 • Total
262,975
 • Density37.565/km2 (97.293/sq mi)
 
Time zoneUTC+8 (ICST)
Area code(+62) 387
Websitesumbatimurkab.go.id

East Sumba Regency (Indonesian: Kabupaten Sumba Timur) is geographically the largest of the four regencies which divide the island of Sumba, within East Nusa Tenggara Province of Indonesia. It occupies 62% (nearly two-thirds) of the entire island, being much less densely populated than the western third. The town of Waingapu is the capital of East Sumba Regency (its urban area comprises the kecamatan of Kota Waingapu and Kambera). The population of East Sumba Regency was 227,732 at the 2010 Census and 244,820 at the 2020 Census; the official estimate as at mid 2025 was 262,975 (comprising 134,682 males and 128,293 females).