What is the county seat of Wyandot County?

The county seat of Wyandot County is Upper Sandusky.

Is there an online parcel map for Wyandot County?

Yes. Ohio Geographically Referenced Information Program (OGRIP, Ohio DAS) statewide compilation of county auditor parcels publishes a parcel map of 20,279 parcels, rated fallback here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Wyandot County's boundary or name changed?

Wyandot County was created in 1845 from Crawford County, Hancock County, Hardin County and Marion County. The Atlas of Historical County Boundaries records no boundary change since.

Who issues building permits in Wyandot County?

The county's page on building permits: Permits. Inside a city or town, ask that city first.

Is my lot in a flood zone?

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

County · code 39175

Wyandot CountyOhio

Wyandot County is a county in Ohio with its seat at Upper Sandusky. It was formed on April 7, 1845, from parts of Crawford, Hancock, Hardin, and Marion counties.

Founded1845
County seatUpper Sandusky
Named forWyandot people
Land area407 sq mi + 0.7 sq mi water
Population21,900 2020 Census
Parcels mapped20,279 checked 14 October 2026

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

Updated 19 October 2026

Census outline · seat marked

History

Formed in 1845 from Crawford County, Hancock County, Hardin County and Marion County

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

Wyandot County was created from Crawford, Hancock, Hardin, and Marion counties. The county was named after the Wyandot people.

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

1845
Wyandot County created Wyandot created from Crawford, Hancock, Hardin, and Marion.
from Crawford from Hancock from Hardin from Marion
7 April 1845 · Ohio Laws 1844, 43d assy., loc., secs. 1-2, 4/pp. 61-62

Land and parcels

What the maps cover in Wyandot

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

Parcels Fallback

Lot lines and tax-map numbers for 20,279 parcels from Ohio Geographically Referenced Information Program (OGRIP, Ohio DAS) statewide compilation of county auditor parcels. Drawn for tax purposes: usually within a few feet of a survey, but not a survey. This copy is a fallback, not the county's own: use it as a guide and check the official record.
edited 23 September 2026 · checked 14 October 2026
Address points Official

One point per address, 11,071 in all from Ohio Geographically Referenced Information Program (OGRIP), Ohio DAS/OIT (state GIS office).
edited 24 June 2025 · 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

Wyandot by the Census

Population

21,900 2020 Census count

Housing units

9,839 2020 Census count

Land area

407 square miles

Water area

0.7 square miles

People per sq mi

54 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

Who to ask before you build, dig or sell

Official county pages only. We link to them; we do not copy them, because they change.

Inside a city or town, permits usually come from that city rather than the county.

Records

Clerk of court: deeds and plats
Clerk of Courts Office
from co.wyandot.oh.us · checked 14 October 2026

Permits

Permitsfrom co.wyandot.oh.us

Zoning and code

Planning and zoningfrom co.wyandot.oh.us · checked 14 October 2026

GIS and maps

County GIS and mapsfrom co.wyandot.oh.us · checked 14 October 2026

County government

County government
The official website of Wyandot County.
co.wyandot.oh.us

See your own lot on these maps

Open Wyandot 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 Wyandot County

When was Wyandot County founded?: Wyandot County was founded in 1845, formed from Crawford County, Hancock County, Hardin County and Marion County, and named after Wyandot people.
What is the county seat of Wyandot County?: The county seat of Wyandot County is Upper Sandusky.
Is there an online parcel map for Wyandot County?: Yes. Ohio Geographically Referenced Information Program (OGRIP, Ohio DAS) statewide compilation of county auditor parcels publishes a parcel map of 20,279 parcels, rated fallback here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Wyandot County's boundary or name changed?: Wyandot County was created in 1845 from Crawford County, Hancock County, Hardin County and Marion County. The Atlas of Historical County Boundaries records no boundary change since.
Who issues building permits in Wyandot County?: The county's page on building permits: Permits. Inside a city or town, ask that city first.
Is my lot in a flood zone?: We do not have flood maps for Wyandot County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby