In the United States, counties are the political subdivisions of a state. Depending on the state, counties may provide certain services to the public, impose taxes, and administer and enforce selected state laws and regulations as well as a court system (or provide regional boundaries for a state court system). In many states, certain government functions and services (as well as taxing authority) are further decentralized below the county level by dividing counties into incorporated municipalities such as cities and towns and/or unincorporated areas. Some types of subdivisions, such as townships, may be either incorporated or unincorporated (or both), depending on the state. The city, town, or populated place that houses county government is known as the seat of its respective county. Generally, the county legislature, county courthouse, sheriff's department headquarters, hall of records and jail and/or correctional facility are located in the county seat, though some functions may also be located or conducted in other parts of the county, especially if it is geographically large.
A county seat is usually, but not always, an incorporated municipality. The exceptions include the county seats of counties that have no incorporated municipalities within their borders, such as Arlington County, Virginia, and Howard County, Maryland. (Ellicott City, the county seat of Howard County, is the largest unincorporated county seat in the United States, followed by Towson, the county seat of Baltimore County, Maryland.) Likewise, some county seats may not be incorporated in their own right, but are located within incorporated municipalities. For example, Cape May Court House, New Jersey, though unincorporated, is a section of Middle Township, an incorporated municipality. In some of the colonial states, county seats include or formerly included "Court House" as part of their name, (e.g. Spotsylvania Courthouse, Virginia).
Most counties have only one county seat. However, some counties in Alabama, Arkansas, Georgia, Iowa, Kentucky, Massachusetts, Mississippi, Missouri, New Hampshire, and Vermont have two or more county seats, usually located on opposite sides of the county. An example is Harrison County, Mississippi, which lists both Biloxi and Gulfport as county seats. The practice of multiple county seat towns dates from the days when travel was difficult. There have been few efforts to eliminate the two-seat arrangement, since a county seat is a source of pride (and jobs) for the towns involved.
There are 36 counties with multiple county seats (no more than two each) in 11 states:Coffee County, Alabama
St. Clair County, Alabama
Arkansas County, Arkansas
Carroll County, Arkansas
Clay County, Arkansas
Craighead County, Arkansas
Franklin County, Arkansas
Logan County, Arkansas
Mississippi County, Arkansas
Prairie County, Arkansas
Sebastian County, Arkansas
Yell County, Arkansas
Columbia County, Georgia
Lee County, Iowa
Campbell County, Kentucky
Kenton County, Kentucky
Essex County, Massachusetts
Middlesex County, Massachusetts
Plymouth County, Massachusetts
Bolivar County, Mississippi
Carroll County, Mississippi
Chickasaw County, Mississippi
Harrison County, Mississippi
Hinds County, Mississippi
Jasper County, Mississippi
Jones County, Mississippi
Panola County, Mississippi
Tallahatchie County, Mississippi
Yalobusha County, Mississippi
Jackson County, Missouri
Hillsborough County, New Hampshire
Seneca County, New York
Bennington County, Vermont
Guilford County, North Carolina, in some ways effectively has two county seats. For example, the official county seat is Greensboro, but an additional courthouse has been located in nearby High Point since 1938.
Other counties in the United States effectively have two or more county seats by establishing one or more branch courthouses at which county business, including the recordation of documents affecting real estate, may be transacted. For example, Clearwater is the county seat of Pinellas County, Florida, but there is a branch courthouse in St. Petersburg.
In New England, the town, not the county, is the primary division of local government. Historically, counties in this region have served mainly as dividing lines for the states' judicial systems. Connecticut (since 1960) and Rhode Island have no county level of government and thus no county seats. In Vermont, Massachusetts, and Maine the county seats are legally designated shire towns. County government consists only of a Superior Court and Sheriff (as an officer of the court), both located in the respective shire town. Bennington County has two shire towns (Manchester for the North Shire, Bennington for the South Shire), but the Sheriff is located in Bennington. In Massachusetts, most government functions which would otherwise be performed by county governments in other states are performed by town governments (there are no unincorporated areas in the state, that is, all land area in the state is within a town). As such, Massachusetts has dissolved many of its county governments, and the state government now operates the registries of deeds and sheriff's offices in those former counties.
In Virginia, a county seat may be an independent city surrounded by, but not part of, the county of which it is the administrative center; for example, Fairfax City is both the county seat of Fairfax County and is completely surrounded by Fairfax County, but the city is politically independent of the county.
Two counties in South Dakota (Oglala Lakota and Todd) have their county seat and government services centered in a neighboring county. Their county-level services are provided by Fall River County and Tripp County, respectively.
In Louisiana, which is divided into parishes rather than counties, county seats are referred to as parish seats.
Alaska is divided into boroughs rather than counties; the county seat in these case is referred to as the "borough seat"; this includes six consolidated city-borough governments and one municipality. The Unorganized Borough, which covers 49% of Alaska's area, has no county seat or equivalent.
In the Canadian Provinces of Prince Edward Island, New Brunswick and Nova Scotia, the term "shire town" is used in place of county seat.
The state with the greatest number of counties is Texas, with 254, and the state with the least number of counties is Delaware, with 3.