| Official Name: | East Kotawaringin Regency |
| Native Name: | Kabupaten Kotawaringin Timur |
| Native Name Lang: | id |
| Settlement Type: | Regency |
| Motto: | "Habaring Hurung" Ngaju language: "Mutual Cooperation and Assistance" |
| Pushpin Map: | Indonesia_Kalimantan#Indonesia |
| Pushpin Label Position: | bottom |
| Pushpin Map Caption: | Location in Kalimantan and Indonesia |
| Subdivision Type: | Country |
| Subdivision Name: | Indonesia |
| Subdivision Type1: | Region |
| Subdivision Name1: | Kalimantan |
| Subdivision Type2: | Province |
| Subdivision Name2: | Central Kalimantan |
| Subdivision Type3: | Capital |
| Subdivision Name3: | Sampit |
| Leader Title: | Regent |
| Leader Name: | Halikinnor |
| Leader Title1: | Vice Regent |
| Leader Name1: | Irawati |
| Unit Pref: | Imperial |
| Area Total Km2: | 16796 |
| Population As Of: | mid 2023 estimate |
| Population Note: | [1] |
| Population Total: | 443459 |
| Population Density Km2: | auto |
| Timezone: | Western Indonesia Time |
| Utc Offset: | +7 |
| Coordinates: | -2.0833°N 112.75°W |
| Area Code Type: | Area code |
| Area Code: | (+62) 531 |
East Kotawaringin Regency (Indonesian: Kabupaten Kotawaringin Timur) is one of the thirteen regencies which comprise the Central Kalimantan Province on the island of Kalimantan (Borneo), Indonesia. It originally covered a much larger part of the province, having been split from a single Kotawaringin Regency on 26 June 1959 into separate regencies for East and West Kotawaringin, but on 10 April 2002 several districts in the west of the regency were split off to form the new Seruyan Regency, and several districts in the east of the regency were similarly split off to form the new Katingan Regency. The area of the residual East Kotawaringin Regency is 16,796 km2, and its population was 374,175 at the 2010 Census,[2] and 428,900 at the 2020 Census;[3] the official estimate as at mid 2023 was 443,359 (comprising 229,220 males and 214,139 females).[4] The town of Sampit is the capital of East Kotawaringin Regency.
At the 2010 Census, East Kotawaringin Regency consisted of fifteen districts (kecamatan), but two more districts (Tualan Hulu and Telaga Antang) were subsequently established by the splitting of existing districts. The seventeen districts are tabulated below with their areas and population totals from the 2010 Census[5] and the 2020 Census,[6] together with the official estimates as at mid 2023.[7] The table also includes the locations of the district administrative centres, the number of administrative villages in each district (totaling 168 rural desa and 17 urban kelurahan), and its postal codes.
| Kode Wilayah | Name of District (kecamatan) | Area in km2 | Pop'n Census 2010 | Pop'n Census 2020 | Pop'n Estimate mid 2023 | Admin centre | No. of villages | Post codes | |
|---|---|---|---|---|---|---|---|---|---|
| 62.02.08 | Mentaya Hilir Selatan (South Lower Mentaya) | 318.00 | 20,801 | 23,010 | 23,163 | Samuda | 10 (a) | 74363 | |
| 62.02.11 | Teluk Sampit (Sampit Bay) | 610.00 | 8,935 | 10,562 | 10,839 | Ujung Pandaran | 6 | 74364 | |
| 62.02.09 | Pulau Hanaut (Hanaut Island) | 620.00 | 15,473 | 16,809 | 16,832 | Bapinang | 14 | 74362 | |
| 62.02.06 | Mentawa Baru Ketapang | 726.00 | 76,951 | 98,680 | 103,688 | Sampit | 11 (b) | 74321 - 76326 | |
| 62.02.12 | Seranau | 548.00 | 9,587 | 10,874 | 11,026 | Mentaya Seberang | 6 (c) | 74314 - 74315 (d) | |
| 62.02.07 | Mentaya Hilir Utara (North Lower Mentaya) | 725.00 | 15,840 | 18,780 | 19,289 | Bagendang | 7 | 74361 | |
| 62.02.01 | Kota Besi | 1,889.00 | 14,980 | 18,444 | 19,153 | Kota Besi | 11 (e) | 74353 | |
| 62.02.14 | Telawang | 317.00 | 16,823 | 20,518 | 21,248 | Sebabi | 6 | 74350 | |
| 62.02.05 | Baamang | 639.00 | 51,538 | 69,714 | 74,397 | Baamang | 6 (f) | 74311 - 74316 | |
| 62.02.02 | Cempaga | 1,253.00 | 19,076 | 22,297 | 22,807 | Cempaga Mulia | 8 | 74354 | |
| 62.02.13 | Cempaga Hulu (Upper Cempaga) | 1,183.00 | 23,262 | 21,586 | 21,871 | Pundu | 11 | 74359 | |
| 62.02.04 | Parenggean | 493.15 | 35,608 | 26,628 | 26,819 | Parenggean | 15 (c) | 74355 | |
| 62.02.16 | Tualan Hulu (Upper Tualan) | 1,095.85 | (g) | 7,766 | 7,868 | Luwuk Sampun | 11 | 74358 | |
| 62.02.03 | Mentaya Hulu (Upper Mentaya) | 1,712.79 | 28,522 | 20,533 | 20,804 | Kuala Kuayan | 16 (c) | 74357 | |
| 62.02.15 | Bukit Santuai | 1,636.00 | 8,038 | 10,380 | 10,929 | Tumbang Penyahuan | 14 | 74356 | |
| 62.02.10 | Antang Kalang | 1,579.00 | 28,741 | 13,357 | 13,533 | Tumbang Kalang | 15 | 74352 | |
| 62.02.17 | Telaga Antang (Lake Antang) | 1,456.21 | (h) | 18,957 | 19,093 | Tumbang Mangkup | 18 | 74352 (i) | |
| Totals | 16,796.00 | 374,175 | 428,895 | 443,359 | Sampit | 185 |
Notes: (a) comprises 2 kelurahan (Samuda Kota and Basirih Hilir) and 8 desa. (b) comprises 5 kelurahan (Ketapang, Mentawa Baru Hilir, Mentawa Baru Hulu, Pasir Putih and Sawahan) and 6 desa. (c) including one kelurahan (the district admin centre).
(d) except for the village of Mentaya Seberang, which has a post code of 74324.
(e) comprises 2 kelurahan (Kota Besi Hilir and Kota Besi Hulu) and 9 desa.
(f) comprises 5 kelurahan (Baamang Barat, Baamang Hilir, Baamang Hulu, Baamang Tengah and Tanah Mas) and 1 desa.
(g) the 2010 population of Tualan Hulu District is included in the figures for the districts from which it was cut out.
(h) the 2010 population of Telaga Antang District is included in the figure for Antang Kalang District.
(i) except for the village of Buana Mustika, which has a post code of 74356.