According to the United States Census Bureau, the city has a total area of 0.57 square miles (1.48 km2), all land.

[6] Tetonia was established as an agricultural town in the late 19th century, taking its name from the nearby Teton Range.

[8] Many of the businesses previously operating in Haden relocated to Tetonia following the arrival of the Union Pacific railroad.

There were 122 housing units at an average density of 214.0 per square mile (82.6/km2).

28.4% of all households were made up of individuals, and 10.5% had someone living alone who was 65 years of age or older.