When was Mercer County founded?

Mercer County was founded in 1837, formed from Giles County and Tazewell County, and named after Hugh Mercer.

What is the county seat of Mercer County?

The county seat of Mercer County is Princeton.

Is there an online parcel map for Mercer County?

Yes. West Virginia University GIS Technical Center publishes a parcel map of 45,635 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Mercer County's boundary or name changed?

Mercer County was created in 1837 from Giles County and Tazewell County. Since then the Atlas of Historical County Boundaries records 3 later changes, chiefly involving Giles (Va.) County and Summers County.

Is my lot in a flood zone?

We do not have flood maps for Mercer County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

County · code 54055

Mercer CountyWest Virginia

Mercer County is a county in West Virginia, with its seat in Princeton. It was created by Virginia on March 17, 1837, from Giles and Tazewell counties, and separated from Virginia to become part of West Virginia in 1863.

Founded1837
County seatPrinceton
Named forHugh Mercer
Land area419 sq mi + 1.7 sq mi water
Population59,664 2020 Census
Parcels mapped45,635 checked 16 October 2026

Open the free map Click any parcel in Mercer County: acreage, parcel id, address and who publishes the map. No sign-in.

Updated 20 October 2026

Census outline · seat marked

History

Formed in 1837 from Giles County and Tazewell County

An old deed may name a county that no longer exists, or a boundary that has since moved.

Mercer County was created by Virginia on March 17, 1837, from Giles and Tazewell counties and named after Hugh Mercer. It lost territory to Giles County in 1841 and to the newly created Summers County in 1871. When Virginia separated in 1863, Mercer County became part of the new state of West Virginia.

Boundary changes from the Newberry Library, Atlas of Historical County Boundaries.

1837
Mercer County created Mercer created by Virginia from Giles (Virginia) and Tazewell Va.).
from Giles (Va.)from Tazewell
17 March 1837 · Va. Acts 1836-1837, ch. 53, sec. 1/pp. 31-33
1841
Lost territory Mercer lost to Giles (Virginia).
to Giles (Va.)
5 March 1841 · Va. Acts 1840-1841, ch. 45, sec. 1/pp. 61-62
1847
Boundary clarified Boundaries of Mercer clarified (no change).
no change
13 March 1847 · Va. Acts 1846-1847, ch. 59, sec. 1/pp. 57-58
1863
Became part of West Virginia Mercer separated from Virginia and became a county in the state of West Virginia. 20 June 1863 · Swindler, 10:363
1871
Lost territory Mercer lost to creation of Summers.
to Summers
27 February 1871 · W. Va. Acts 1871, 9th sess., ch. 134, sec. 1/pp. 178-180

Land and parcels

What the maps cover in Mercer

Who publishes each layer, how good it is, and when we last checked.

Parcels Good enough

Lot lines and tax-map numbers for 45,635 parcels from West Virginia University GIS Technical Center. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 16 October 2026
Address points Official

One point per address, 34,429 in all from WV GIS Technical Center (WVGISTC, West Virginia University — the state's GIS clearinghouse) serving WV Division of Homeland Security and Emergency Management (WVDHSEM) SAMS-II address points.
checked 13 October 2026
Buildings Reference

Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026

Official: from the office that keeps the record
Good enough: a reliable statewide or national copy
Fallback: a guide only; check the official record
Missing: nothing public found yet

People and land

Mercer by the Census

Population

59,664 2020 Census count

Housing units

29,321 2020 Census count

Land area

419 square miles

Water area

1.7 square miles

People per sq mi

142 population ÷ land area

Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.

Rules and offices

Mercer County's official site

We have found the county's site but not its offices yet; start there.

County government

County government
The official website of Mercer County.
mercercounty.wv.gov

See your own lot on these maps

Open Mercer County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.

Open the free map no sign-in Pro early access

Questions

Common questions about Mercer County

When was Mercer County founded?: Mercer County was founded in 1837, formed from Giles County and Tazewell County, and named after Hugh Mercer.
What is the county seat of Mercer County?: The county seat of Mercer County is Princeton.
Is there an online parcel map for Mercer County?: Yes. West Virginia University GIS Technical Center publishes a parcel map of 45,635 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Mercer County's boundary or name changed?: Mercer County was created in 1837 from Giles County and Tazewell County. Since then the Atlas of Historical County Boundaries records 3 later changes, chiefly involving Giles (Va.) County and Summers County.
Is my lot in a flood zone?: We do not have flood maps for Mercer County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby