Trans Nzoia County lies on the western side of Mount Elgon in the former Rift Valley province, some 380 km north west of Nairobi.
The county borders Bungoma to the west, Uasin Gishu and Kakamega to the south, Elgeyo Marakwet to the east, West Pokot to the north and the republic of Uganda to North West. Trans Nzoia covers an area of 2495.5 square kilometres.
The Trans Nzoia County is divided in five electoral regions: Cherangany, Saboti, Kwanza, Kiminini and Endebess constituencies. The top county leaders are George Natembeya (Governor), Philomenah Bineah (deputy governor), Allan Chesang (Senator) and Lilian Siyoi (women representative).
Other top leaders in the National Assembly are Kakai Bisau (Kiminini-MP), Ferdinand Wanyonyi (Kwanza-MP), Robert Pukose (Endebess-MP), Caleb Amisi (Saboti-MP) and Simiyu Patrick (Cherangany-MP).