Myers Flat is a census-designated place in Humboldt County, California. It is located 4.5 miles south-southeast of Weott, at an elevation of 203 feet. The ZIP Code is 95554. The population was 146 at the 2010 census.Originally called Myers from the Grant Myers Ranch, "Flat" was added to the name to distinguish the place from Meyers in El Dorado County.The Myers Flat post office opened in 1949.Myers Flat is located along the California State Route 254, also known as Avenue of the Giants. The US Post Office's ZIP Code is 95554. The community is inside area code 707.