Ottosen Map
Ottosen is a city in Humboldt County, Iowa, United States. The population was 55 in the 2010 census, a decline from 61 in 2000.
Much of the town burned in a fire in the mid-1900s and was never rebuilt.
According to the United States Census Bureau, the city has a total area of 0.6 square miles (1.5 km²), all of it land.
Nearby cities include Livermore, Rutland, Gilmore City, Whittemore, Plover.