Yankton County is a county in South Dakota. It covers 533 square miles (340,902 acres), which represents less than one percent of the state total. Of the 66 counties in South Dakota, Yankton County ranks ninth in terms of the size of its population (22,702, according to 2015 Census estimates). Manufacturing and related services provide the main economic inputs to Yankton County. Recent Lands of America data shows that the average price-per-acre value of land for sale in Yankton County is $19,510. The average list price of property and land for sale was $151,357 (the most expensive listing being for $935,000) and the median acreage of land for sale in Yankton County was one acre. Land for sale in Yankton County totaled 473 acres and $9.2 million in overall land value. Farmland was the most common type of land for sale in Yankton County.