Khok Sa-at () is a tambon (subdistrict) of Nam Khun district, in Ubon Ratchathani Province, Thailand. The subdistrict was established in 1991 through the separation of seven administrative communities () from the southwestern portion of tambon Ta Kao.
As of the 2025 consensus, the subdistrict had a population of 6,792, distributed across 9 villages (Muban; à ¸Âà ¹Âà ¸²à ¸ or à ¸«à ¸¡à ¸¹à ¹Âà ¸Âà ¹Âà ¸²à ¸Â), which are further organized into 12 administrative communities (). It covers an area of 92.74 sqoare kilometeres.
Khok Sa-at is bordered by the following neighboring jurisdictions, listed clockwise from the south: Choam Khsant District of Cambodia, Phu Pha Mok, Non Samran, Phaibun, Ta Kao, and Song.
Prior to 1912, the areaâÂÂthen administratively part of Ta Kao SubdistrictâÂÂwas governed under , a former provincial unit of Thailand. In 1912, following administrative reorganization, the area was transferred to Det Udom District, and Det Udom itself was transferred from to Ubon Ratchathani province. Subsequently, in 1974, the territory of Ta Kao Subdistrict was separated from Det Udom District and incorporated into the newly established Nam Yuen District, together with three other subdistricts formerly under Det Udom.
In 1991, Khok Sa-at attained subdistrict status through the separation of the southwestern portion of Ta Kao Subdistrict. Later in 1996, Khok Sa-atâÂÂalong with its three administratively related subdistricts, Ta Kao, Phaibun, and KhilekâÂÂwas separated from Nam Yuen District to form Nam Khun District.
During the initial phase of its establishment, the subdistrict was governed by the Khok Sa-at Subdistrict Council (), functioning as the local administrative authority in accordance with the prevailing framework of Thai local administration. In 1997, the council was formally reorganized and upgraded to the status of the Khok Sa-at Subdistrict Administrative Organization ().
The subdistrict of Khilek is subdivided into 9 villages (mubans; ) and 13 administrative communities (Moo or Mu;). As of the 2025 census, it had a population of 8,755 people. The entire tambon is governed by the Khok Sa-at Subdistrict Administrative Organization.
The following is a list of the subdistrict's mubans, which roughly correspond to the villages.