According to the United States Census Bureau, the township has a total area of 35.5 square miles (92.0 km²), all land.

Main highways include: Organization of Willmont Township (note the double-L) was approved by the Nobles County Board on November 12, 1878.

There was a general disagreement over the township name, one faction wishing to call it Willumet, and the other favoring Lamont.

Wilmont Township is located in Minnesota's 1st congressional district, represented by Mankato educator Tim Walz, a Democrat.

Wilmont Township is represented by Nobles County Commissioner Gene Metz.