[3] The Ionia County Courthouse was designed by Claire Allen, a prominent southern Michigan architect.

Ionia County is part of the Grand Rapids-Kentwood metropolitan statistical area.

The county government operates the jail, maintains rural roads, operates the major local courts, records deeds, mortgages, and vital records, administers public health regulations, and participates with the state in the provision of social services.

The county board of commissioners controls the budget and has limited authority to make laws or ordinances.

In Michigan, most local government functions—police and fire, building and zoning, tax assessment, street maintenance, etc.—are the responsibility of individual cities and townships.

(information as of February 2023[update]) Public school districts serving Ionia County include:[21]