In 1778, Vermont had only two counties:
- Bennington County: formed in 1778 as one of two original counties, and comprised the western side of the state. County seat: Bennington
- Orange County: formed in 1778 as Unity County -- one of two original counties, and comprised the eastern side of the state. Renamed Orange County in 1781. County seat: Chelsea
The two counties were split into five as of 1781:
- Rutland County: formed in 1781 from the northern part of Bennington County. County seat: Rutland
- Windham County: formed in 1781 from part of Unity (Orange) County. County seat: Newfane
- Windsor County: formed in 1781 from part of Unity (Orange) County. County seat: Woodstock
- Addison County: formed in 1785 from part of Rutland County. County seat: Middlebury
- Chittenden County: formed in 1787 from part of Addison County. County seat: Burlington
- Franklin County: formed in 1791 from part of Chittenden County. County seat: St. Albans
- Grand Isle County: formed in 1805 from part of Franklin County. County seat: North Hero
- Washington County: formed in 1810 from parts of Addison County, Caledonia County, Chittenden County, and Orange County. County seat (and the state capital): Montpelier
- Lamoille County: formed in 1835 from parts of Chittenden County, Franklin County, Orleans County. County seat: Hyde Park
- Essex County: formed in 1791 from part of Orange County. County seat: Guildhall
- Orleans County: formed in 1791 from part of Orange County. County seat: Newport
- Caledonia County: formed in 1796 from part of Orange County. County seat: St. Johnsbury