County · code 17055
Franklin CountyIllinois
Franklin County is in southern Illinois, with its county seat at Benton. The county was formed in 1818 and named after Benjamin Franklin.
- Founded1818
- County seatBenton, Illinois
- Named forBenjamin Franklin
- Land area409 sq mi + 23 sq mi water
- Population37,804 2020 Census
- Parcels mapped31,478 checked 15 October 2026
Where it is
Franklin 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 1818 from Gallatin County, Johnson County and White County
An old deed may name a county that no longer exists, or a boundary that has since moved.
Franklin County was created on January 2, 1818, by the Illinois Territory from parts of Gallatin, Johnson, and White counties. When Illinois became a state later that year, Franklin became a county within it. The county lost territory in 1839 with the creation of Williamson County.
- 1818Franklin County created Franklin created by Illinois Territory from Gallatin, Johnson, and White. · Ill. Terr. Laws, 290-291
- 1818Became part of Illinois Franklin became a county in the state of Illinois when Illinois was created from Illinois Territory. · Terr. Papers U.S., 10:803; U.S. Stat., vol. 3, ch. 67 [1818], secs. 1-2, 7/pp. 428-429, 431, and res. 1 [1818]/p. 536
- 1835
- 1839Lost territory Franklin lost to creation of Williamson. · Ill. Laws 1838-1839, pp. 110-113
Land and parcels
What the maps cover in Franklin
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 31,478 parcels from Franklin County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
edited 15 September 2026 · checked 15 October 2026 -
Address points Missing
No public address points layer found for Franklin 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
Franklin 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
Franklin 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 Franklin County.
See your own lot on these maps
Open Franklin 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 Franklin County
- When was Franklin County founded?
- Franklin County was founded in 1818, formed from Gallatin County, Johnson County and White County, and named after Benjamin Franklin.
- What is the county seat of Franklin County?
- The county seat of Franklin County is Benton, Illinois.
- Is there an online parcel map for Franklin County?
- Yes. Franklin County publishes a parcel map of 31,478 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Franklin County's boundary or name changed?
- Franklin County was created in 1818 from Gallatin County, Johnson County and White County. Since then the Atlas of Historical County Boundaries records 3 later changes, chiefly involving Perry County and Williamson County.
- Is my lot in a flood zone?
- We do not have flood maps for Franklin County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby