Grimes (formerly, Grimes Landing) is a census-designated place in Colusa County, California on the Southern Pacific Railroad. It lies at an elevation of 46 feet (14 m). On the outskirts of Grimes there is wildlife such as jackrabbits and coyotes. The two main roads that run through it are State Route 45 and Grimes-Arbuckle Road. Its ZIP code is 95950, and its area code is 530. Grimes's population was 391 at the 2010 census.
The post office was established in 1883. Grimes is named after Cleaton Grimes, who obtained the townsite land in 1844.