A rural county is defined as a county with a population density of fewer than 100 persons per square mile or a county smaller than 225 square miles, as determined by the Office of Financial Management.
Several statutes use this definition, including but not limited to statutes referencing public facilities loans and grants, the coordination of community and economic development services, and excise taxes. As of 2025, there are 29 rural counties.
The definition of rural county is expanded such that a county with a population density of 100 persons per square mile or greater, with no city with a population greater than 45,000 persons, is also defined as a rural county.