County · code 55073
Marathon CountyWisconsin
Marathon County is a county in Wisconsin with its county seat in Wausau. The county was created in 1850 from Portage County and is named after the Battle of Marathon.
- Founded1850
- County seatWausau
- Named forBattle of Marathon
- Land area1,545 sq mi + 31 sq mi water
- Population138,013 2020 Census
- Parcels mapped83,408 checked 16 October 2026
Where it is
Marathon on the map of Wisconsin
Wisconsin has 72 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Formed in 1850 from Portage County
An old deed may name a county that no longer exists, or a boundary that has since moved.
Marathon County was created from Portage County on February 16, 1850. In 1860, it gained territory from Oconto and Shawano counties. Beginning in 1875, Marathon County lost territory to the creation of Lincoln and Taylor counties; Lincoln was initially attached to Marathon for judicial purposes before being fully organized and detached in May 1875.
- 1850Marathon County created Marathon created from Portage. · Wis. Laws 1850, ch. 226, secs. 1-2, 14/pp. 180-181
- 1860Gained territory Marathon gained from Oconto and Shawano. · Wis. Laws 1860, gen., ch. 120, secs. 1-2/p. 107
- 1875Lost territory Marathon lost to creation of Lincoln; Lincoln not fully organized, attached to Marathon "for all judicial purposes." · Wis. Laws 1874, ch. 128, secs. 1-2, 5/pp. 256-258
- 1875Lost territory Marathon lost to creation of Taylor. · Wis. Laws 1875, ch. 178, secs. 1-3, 11/pp. 297-300
- 1875Changed Lincoln fully organized, detached from Marathon. · Wis. Laws 1875, ch. 60, secs. 1, 5/pp. 138-139
Land and parcels
What the maps cover in Marathon
Who publishes each layer, how good it is, and when we last checked.
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Parcels Good enough
Lot lines and tax-map numbers for 83,408 parcels from Marathon County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 16 October 2026 -
Address points Missing
No public address points layer found for Marathon County yet.
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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
Marathon by the Census
Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.
Rules and offices
Marathon 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 Marathon County.
See your own lot on these maps
Open Marathon 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.
Questions
Common questions about Marathon County
- When was Marathon County founded?
- Marathon County was founded in 1850, formed from Portage County, and named after Battle of Marathon.
- What is the county seat of Marathon County?
- The county seat of Marathon County is Wausau.
- Is there an online parcel map for Marathon County?
- Yes. Marathon County publishes a parcel map of 83,408 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Marathon County's boundary or name changed?
- Marathon County was created in 1850 from Portage County. Since then the Atlas of Historical County Boundaries records 4 later changes, chiefly involving Lincoln County, Oconto County and Shawano County.
- Is my lot in a flood zone?
- We do not have flood maps for Marathon County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby