Richwood Precinct is located in Calhoun County, Illinois.

[2] As of the 2020 census[3] there were 778 people, 346 households, and 297 families residing in the precinct.

There were 360 housing units at an average density of 8.56 per square mile (3.31/km2).

The racial makeup of the precinct was 97.17% White, 0.00% African American, 0.00% Native American, 0.13% Asian, 0.00% Pacific Islander, 0.00% from other races, and 2.70% from two or more races.

13.60% of all households were made up of individuals, and 9.80% had someone living alone who was 65 years of age or older.