Lagat is a surname. Notable people with the surname include: Bernard Lagat (born 1974), Kenyan-American middle- and long-distance runner Cleophas Lagat, Kenyan politician and Governor of Nandi County Elijah Lagat (1966–2025), Kenyan marathon runner and politician Viola Cheptoo Lagat (born 1989), Kenyan middle-distance runner
See also Langat (surname), a related Kalenjin surname