County · code 17067
Hancock CountyIllinois
Hancock County is in Illinois, with its seat in Carthage. It was created on January 13, 1825, and named after John Hancock.
- Founded1825
- County seatCarthage
- Named forJohn Hancock
- Land area794 sq mi + 21 sq mi water
- Population17,620 2020 Census
- Parcels mapped21,182 checked 16 October 2026
Where it is
Hancock on the map of Illinois
Illinois has 102 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Formed in 1825 from Pike County and Adams County
An old deed may name a county that no longer exists, or a boundary that has since moved.
Hancock County was created from Pike and Adams counties, initially not fully organized and attached to Adams for county purposes. It became fully organized and independent on August 3, 1829. In 1837, the county's boundaries were extended to the middle of the Mississippi River.
- 1825Hancock County created Hancock created from Non-County Area 3 attached to Pike; Hancock not fully organized, attached to Adams "for county purposes." · Ill. Laws 1824-1825, pp. 85-87, 92-96
- 1829
- 1837Changed Hancock boundaries were extended to the middle of the Mississippi River. · Ill. Laws 1836-1837, pp. 91-92
Land and parcels
What the maps cover in Hancock
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 21,182 parcels from Hancock County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
edited 9 July 2026 · checked 16 October 2026 -
Address points Missing
No public address points layer found for Hancock 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
Hancock 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
Hancock 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 Hancock County.
See your own lot on these maps
Open Hancock 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 Hancock County
- When was Hancock County founded?
- Hancock County was founded in 1825, formed from Pike County and Adams County, and named after John Hancock.
- What is the county seat of Hancock County?
- The county seat of Hancock County is Carthage.
- Is there an online parcel map for Hancock County?
- Yes. Hancock County publishes a parcel map of 21,182 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Hancock County's boundary or name changed?
- Hancock County was created in 1825 from Pike County and Adams County. Since then the Atlas of Historical County Boundaries records 2 later changes, chiefly involving Adams County.
- Is my lot in a flood zone?
- We do not have flood maps for Hancock County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby