Grimes (formerly, Grimes Landing) is an unincorporated community in Colusa County, California on the Southern Pacific Railroad. It lies at an elevation of 46 feet (14 m). Its zip code is 95950 and its area code is 530. The post office was established in 1883. Grimes is named after Cleaton Grimes, who obtained the townsite land in 1844.
In the state legislature Grimes is located in the 4th Senate District, represented by Republican Sam Aanestad, and in the 2nd Assembly District, represented by Republican Doug LaMalfa. Federally, Grimes is located in California's 2nd congressional district, which has a Cook PVI of R +13 and is represented by Republican Wally Herger.