When was Door County founded?

Door County was founded in 1851, formed from Brown County and Manitowoc County, and named after Door Peninsula, Wisconsin.

What is the county seat of Door County?

The county seat of Door County is Sturgeon Bay.

Is there an online parcel map for Door County?

Yes. A public source publishes a parcel map of 43,153 parcels, rated fallback here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Door County's boundary or name changed?

Door County was created in 1851 from Brown County and Manitowoc County. Since then the Atlas of Historical County Boundaries records 7 later changes, chiefly involving U.s. County, Delta (Mich.) County and Brown County.

Who issues building permits in Door County?

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

Who issues septic and well permits in Door County?

The county's page on septic systems and wells: Health department: septic and well.

Is my lot in a flood zone?

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

County · code 55029

Door CountyWisconsin

Door County is a county in Wisconsin, located on the Door Peninsula, with its county seat in Sturgeon Bay. The county was created on February 11, 1851, from parts of Brown and Manitowoc Counties.

Founded1851
County seatSturgeon Bay
Named forDoor Peninsula, Wisconsin
Land area482 sq mi + 1,888 sq mi water
Population30,066 2020 Census
Parcels mapped43,153 checked 15 October 2026

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

Updated 20 October 2026

Census outline · seat marked

History

Formed in 1851 from Brown County and Manitowoc County

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

Door County was created in 1851 from Brown and Manitowoc Counties but was not initially organized, remaining attached to Manitowoc for judicial purposes. In 1852, Door County lost territory to the creation of Kewaunee County, and in 1855 it was detached from Manitowoc and attached to Brown for judicial purposes. The county became fully organized and independent on January 1, 1861, when it detached from Brown. During the early twentieth century, a boundary dispute between Michigan and Wisconsin over islands in Green Bay affected Door County's territory until the U.S. Supreme Court resolved the dispute in Wisconsin's favor in 1926, with final adjustments made in 1936.

Boundary changes from the Newberry Library, Atlas of Historical County Boundaries; the 5 that matter most are shown first.

1851
Door County created Door created from Brown; Door not fully organized, attached to Manitowoc "for judicial purposes."
from Brown from Manitowoc
11 February 1851 · Wis. Laws 1851, ch. 66, sec. 1/p. 50
1852
Lost territory Door lost to creation of Kewaunee.
to Kewaunee
16 April 1852 · Wis. Laws 1852, ch. 363, secs. 1-2/pp. 549-551
1855
Changed Door detached from Manitowoc, attached to Brown "for judicial purposes."
Manitowoc Brown
1 May 1855 · Wis. Laws 1855, priv. and loc., ch. 397, secs. 1, 7/pp. 597-598
1861
Changed Door fully organized, detached from Brown.
Brown
1 January 1861 · Wis. Laws 1860, gen., ch. 236, sec. 1/p. 212
1923
Door County created Delta (Michigan) implicitly overlapped Door when Michigan took its 1909 boundary dispute with Wisconsin to the U.S. Supreme Court and expanded its scope by claiming more of the waters and islands of Green Bay. Wisconsin claimed the old, established line and never lost control of the disputed area. Delta (Michigan) claimed Washington, Rock, Chambers, Plum, and smaller islands in Green Bay.
from Delta (Mich.)from U.s.
8 October 1923 · Martin, "Michigan-Wisconsin," 116, 118, 132

Show all 8 changes (3 more, mostly small adjustments)

1851
Door County created Door created from Brown; Door not fully organized, attached to Manitowoc "for judicial purposes."
from Brown from Manitowoc
11 February 1851 · Wis. Laws 1851, ch. 66, sec. 1/p. 50
1852
Lost territory Door lost to creation of Kewaunee.
to Kewaunee
16 April 1852 · Wis. Laws 1852, ch. 363, secs. 1-2/pp. 549-551
1855
Changed Door detached from Manitowoc, attached to Brown "for judicial purposes."
Manitowoc Brown
1 May 1855 · Wis. Laws 1855, priv. and loc., ch. 397, secs. 1, 7/pp. 597-598
1861
Changed Door fully organized, detached from Brown.
Brown
1 January 1861 · Wis. Laws 1860, gen., ch. 236, sec. 1/p. 212
1923
Door County created Delta (Michigan) implicitly overlapped Door when Michigan took its 1909 boundary dispute with Wisconsin to the U.S. Supreme Court and expanded its scope by claiming more of the waters and islands of Green Bay. Wisconsin claimed the old, established line and never lost control of the disputed area. Delta (Michigan) claimed Washington, Rock, Chambers, Plum, and smaller islands in Green Bay.
from Delta (Mich.)from U.s.
8 October 1923 · Martin, "Michigan-Wisconsin," 116, 118, 132
1926
Changed Michigan's implicit overlap of Door ended when the U.S. Supreme Court decided the boundary dispute between Michigan and Wisconsin entirely in favor of Wisconsin.
U.s.
1 March 1926 · Martin, "Michigan-Wisconsin," 141-143
1926
Changed Door appeared to gain islands north of the Rock Island Passage from Delta (Michigan) when the U.S. Supreme Court decreed the precise course of the Michigan-Wisconsin boundary through Lake Michigan and Green Bay and introduced some unintentional errors.
Delta (Mich.)U.s.
22 November 1926 · Martin, "Michigan-Wisconsin," 143-145, 158; Paullin, 86, pl. 101
1936
Lost territory Door lost control of the area overlapped with Delta (Michigan); dispute with Wisconsin ended when the U.S. Supreme Court decreed the precise course of the revised Michigan-Wisconsin boundary through Green Bay and Lake Michigan, restoring to Delta (Michigan) the area it appeared to lose in 1926.
to Delta (Mich.)to U.s.
16 March 1936 · Martin, "Second Wisconsin-Michigan," 86, 118-121

Land and parcels

What the maps cover in Door

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

Parcels Fallback

Lot lines and tax-map numbers for 43,153 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 17 October 2023 · checked 15 October 2026
Address points Missing

No public address points layer found for Door County yet.
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

Door by the Census

Population

30,066 2020 Census count

Housing units

23,738 2020 Census count

Land area

482 square miles

Water area

1,888 square miles · 80% of the county, including large bodies of water

People per sq mi

62 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
Municipal Clerk Contacts
from co.door.wi.gov · checked 16 October 2026

Permits

Health department: septic and wellfrom co.door.wi.gov · checked 16 October 2026
Driveway Permitfrom co.door.wi.gov
Permits & Licensesfrom co.door.wi.gov
Well Water Test Kitsfrom co.door.wi.gov
Private Well Water Testing Lab Brochurefrom co.door.wi.gov

Zoning and code

Planning and zoningfrom co.door.wi.gov · checked 16 October 2026
Ordinancesfrom co.door.wi.gov
Code of Ordinances from co.door.wi.gov
Zoning Board of Adjustmentfrom co.door.wi.gov

GIS and maps

County GIS and maps 800-450-7240from co.door.wi.gov · checked 16 October 2026

County government

County government
The official website of Door County.
co.door.wi.gov

See your own lot on these maps

Open Door 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 Door County

When was Door County founded?: Door County was founded in 1851, formed from Brown County and Manitowoc County, and named after Door Peninsula, Wisconsin.
What is the county seat of Door County?: The county seat of Door County is Sturgeon Bay.
Is there an online parcel map for Door County?: Yes. A public source publishes a parcel map of 43,153 parcels, rated fallback here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Door County's boundary or name changed?: Door County was created in 1851 from Brown County and Manitowoc County. Since then the Atlas of Historical County Boundaries records 7 later changes, chiefly involving U.s. County, Delta (Mich.) County and Brown County.
Who issues building permits in Door County?: The county's page on building permits: Driveway Permit. Inside a city or town, ask that city first.
Who issues septic and well permits in Door County?: The county's page on septic systems and wells: Health department: septic and well.
Is my lot in a flood zone?: We do not have flood maps for Door County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

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