County Maps US

Sangamon County, Illinois

A county in Illinois, ranked 11 of 102 by population.

CountyFIPS 17167

Within Illinois
Sangamon County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Springfield, the county seat, located via the 2025 Census Gazetteer.

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Population
194,170
-2,032 (-1.0%) since 2020
Land area
868.2
square miles. A further 1.0% of the total area is water
Population density
224
people per square mile, computed rather than published
County seat
Springfield
Seat of county government.
Established
1821
204 years ago
Largest city
Springfield city
Population 112,989.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Sangamon County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Sangamon County, Illinois from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 800 by 629 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Sangamon County ranks

Position among the 102 counties of Illinois, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn IllinoisNationally
Population194,17011th of 102367th of 3,144
Land area868.2 sq mi9th of 102944th of 3,144
Population density224 per sq mi13th of 102530th of 3,144
Median household income$75,35725th of 102821st of 3,143

Full data for Sangamon County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population194,170Vintage 2025 Population Estimates
Population in 2020196,202Vintage 2025 Population Estimates
2020 estimates base?196,405Vintage 2025 Population Estimates
Land area868.2 sq mi2025 Gazetteer Files
Water area8.8 sq mi2025 Gazetteer Files
Total area877 sq mi2025 Gazetteer Files
Population density?224 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$75,357American Community Survey 2020-2024 5-Year Estimates
Median home value$176,300American Community Survey 2020-2024 5-Year Estimates
Median age41.0American Community Survey 2020-2024 5-Year Estimates
Households84,762American Community Survey 2020-2024 5-Year Estimates
Housing units93,382American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
-153
2,008 births, 2,161 deaths
Net migration
+279
More people moved in than moved out.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 8 areas bordering Sangamon County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Christian CountyIllinois42 mi33,443
Menard CountyIllinois27 mi11,863
Morgan CountyIllinois25 mi32,515
Logan CountyIllinois23 mi27,182
Macoupin CountyIllinois12 mi43,748
Montgomery CountyIllinois9.0 mi28,076
Macon CountyIllinois7.1 mi99,300
Cass CountyIllinois2.0 mi12,463

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 102 counties of Illinois

Open the interactive Illinois county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.