Westport is a town in western Brown County, South Dakota, United States.

[6] According to the United States Census Bureau, the town has a total area of 0.24 square miles (0.62 km2), all land.

The racial makeup of the town was 92.5% White, 4.5% Native American, and 3.0% from other races.

25.0% of all households were made up of individuals, and 12.5% had someone living alone who was 65 years of age or older.

22.9% of all households were made up of individuals, and 12.5% had someone living alone who was 65 years of age or older.

There were no families and 2.2% of the population living below the poverty line, including no under eighteens and 5.0% of those over 64.