Ruth is a census-designated place (CDP) in Trinity County, California. Ruth is located in the southern portion of the county. The community - and adjacent Ruth Lake - was named after Ruth McKnight, daughter of settlers. The ZIP code is 95526. The community is inside area code 707. It is located near the headwaters of the Mad River (California) and adjacent to the Yolla Bolly-Middle Eel Wilderness. Ruth sits at an elevation of 2,933 feet (894 m).