The Missouri River flows southward along the west boundary line of Potter County. The county terrain consists of rolling hills, mostly devoted to agriculture. The county generally slopes to the south, although the western portion slopes into the river valley. The county has a total area of, of which is land and is water. The eastern portion of South Dakota's counties observe Central Time; the western counties observe Mountain Time. Potter County is the westernmost of the SD counties to observe Central Time.
As of the 2000 United States Census, there were 2,693 people, 1,145 households, and 767 families in the county. The population density was 3 people per square mile. There were 1,760 housing units at an average density of 2 per square mile. The racial makeup of the county was 98.14% White, 0.82% Native American, 0.19% Asian, 0.07% from other races, and 0.78% from two or more races. 0.19% of the population were Hispanic or Latino of any race. There were 1,145 households out of which 26.60% had children under the age of 18 living with them, 59.20% were married couplesliving together, 4.90% had a female householder with no husband present, and 33.00% were non-families. 31.30% of all households were made up of individuals and 17.50% had someone living alone who was 65 years of age or older. The average household size was 2.29 and the average family size was 2.88. The county population contained 23.00% under the age of 18, 3.90% from 18 to 24, 22.30% from 25 to 44, 25.70% from 45 to 64, and 25.00% who were 65 years of age or older. The median age was 46 years. For every 100 females there were 96.70 males. For every 100 females age 18 and over, there were 94.80 males. The median income for a household in the county was $30,086, and the median income for a family was $37,827. Males had a median income of $25,320 versus $16,563 for females. The per capita income for the county was $17,417. About 8.90% of families and 12.60% of the population were below the poverty line, including 18.00% of those under age 18 and 12.30% of those age 65 or over.
2010 census
As of the 2010 United States Census, there were 2,329 people, 1,062 households, and 648 families in the county. The population density was. There were 1,500 housing units at an average density of. The racial makeup of the county was 97.6% white, 0.9% American Indian, 0.3% Asian, 0.1% black or African American, 0.2% from other races, and 0.9% from two or more races. Those of Hispanic or Latino origin made up 0.7% of the population. In terms of ancestry, 65.3% were German, 11.1% were Irish, 8.2% were Norwegian, 8.0% were English, and 3.9% were American. Of the 1,062 households, 21.7% had children under the age of 18 living with them, 53.0% were married couples living together, 4.2% had a female householder with no husband present, 39.0% were non-families, and 35.5% of all households were made up of individuals. The average household size was 2.13 and the average family size was 2.76. The median age was 50.6 years. The median income for a household in the county was $42,422 and the median income for a family was $53,214. Males had a median income of $33,750 versus $29,792 for females. The per capita income for the county was $23,986. About 5.4% of families and 10.0% of the population were below the poverty line, including 11.7% of those under age 18 and 10.8% of those age 65 or over.
The county has no organized townships. It is divided into three areas of unorganized territory: West Potter, Central Potter, and East Potter.
Politics
Like most of South Dakota outside of Native American counties, Potter County has been powerfully Republican throughout most of the state’s history. Only three Democrats – William Jennings Bryan, Franklin D. Roosevelt and Lyndon Johnson – have carried the county as of 2016, and since Jimmy Carter in 1976 no Democrat has passed forty percent of the county’s vote.
