Frankfort is a city in Spink County, South Dakota, United States.

[8] According to the United States Census Bureau, the city has a total area of 0.79 square miles (2.05 km2), all land.

The racial makeup of the city was 94.6% White, 3.4% Native American, and 2.0% from other races.

32.8% of all households were made up of individuals, and 13.1% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 98.80% White, 0.60% Native American, 0.60% from other races.

About 4.3% of families and 9.2% of the population were below the poverty line, including 18.8% of those under the age of eighteen and 12.2% of those 65 or over.