Richfield Township was organized on November 18, 1881 (effective April 1882). The origin of the name is uncertain, although one report is the name was chosen because the township had fertile soil. As of 2010, there were 1,628 people, 473 households, and 383 families residing in the town. The population density was 43.8 people per square mile (16.9/km). There were 485 housing units at an average density of 13.9/sq mi (5.4/km).
There were 473 households out of which 41.2% had children under the age of 18 living with them, 71.7% were married couples living together, 5.1% had a female householder with no husband present, and 19.0% were non-families. 14.0% of all households were made up of individuals and 5.3% had someone living alone who was 65 years of age or older. The average household size was 2.98 and the average family size was 3.26.
In the town the population was spread out with 27.8% under the age of 18, 6.5% from 18 to 24, 29.1% from 25 to 44, 21.2% from 45 to 64, and 15.4% who were 65 years of age or older. The median age was 36 years.