Lewiston is an unincorporated community in Montmorency County, Michigan, United States. It is a census-designated place (CDP) used for statistical purposes. The population was 990 at the 2000 census. The Lewiston post office first opened on April 25, 1892.
According to the United States Census Bureau, the CDP has a total area of 8.6 square miles (22.2 km²), of which, 5.3 square miles (13.7 km²) of it is land and 3.3 square miles (8.5 km²) of it (38.39%) is water.
As of the census of 2000, there were 990 people, 480 households, and 312 families residing in the CDP. The population density was 187.2 per square mile (72.3/km²). There were 1,230 housing units at an average density of 232.6 per square mile (89.8/km²). The racial makeup of the CDP was 98.59% White, 0.10% African American, 0.20% Native American, 0.61% from other races, and 0.51% from two or more races. Hispanic or Latino of any race were 1.21% of the population.