Letcher is a town in Sanborn County, South Dakota, United States.

There were 83 housing units at an average density of 133.9 per square mile (51.7/km2).

39.0% of all households were made up of individuals, and 15.6% had someone living alone who was 65 years of age or older.

The racial makeup of the town was 97.74% White, 0.56% Asian, 0.56% Pacific Islander, and 1.13% from two or more races.

24.0% of all households were made up of individuals, and 10.7% had someone living alone who was 65 years of age or older.

About 18.6% of families and 24.0% of the population were below the poverty line, including 42.9% of those under the age of eighteen and 10.7% of those 65 or over.