Resident Population in Otter Tail County, MN was 60.88400 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Otter Tail County, MN reached a record high of 60.88400 in January of 2024 and a record low of 46.09700 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Otter Tail County, MN - last updated from the United States Federal Reserve on April of 2026.