Sagamihara (相模原市, Sagamihara-shi) is a city in Kanagawa Prefecture, Japan. As of May 1, 2021, the city has an estimated population of 723,470, with 334,812 households, and a population density of 1,220 persons per km. The total area of the city is 328.91 square kilometres (126.99 sq mi). Sagamihara is the third-most-populous city in the prefecture, after Yokohama and Kawasaki, and the fifth most populous suburb of the Greater Tokyo Area. Its northern neighbor is Machida, with which a cross-prefectural merger has been proposed.
On April 1, 2010, the city became the 19th city designated by government ordinance. As a result of this, three wards were established: Midori-ku, Chūō-ku and Minami-ku.