Kane County, Illinois

Kane County is a county in Illinois, United States, about 40 miles west of downtown Chicago. It
had a population of 516,522 at the 2020 census, an estimated 525,757 by 2025, and covers 524
square miles (1,357 km2) centred near 41°57′N 88°26′W.

Geneva is the county seat; its postal code is 60134. Aurora, largely within Kane County, is the
county’s largest city. The county holds 5 cities and 25 incorporated villages across 16
townships, and it runs on Central Time. Its FIPS code is 17089.

Towns & Villages in Kane County

Kane County has 30 incorporated cities and villages, plus a handful of unincorporated
crossroads communities with no local government of their own. Several of the county’s larger
municipalities — Aurora, Bartlett, Hoffman Estates and Barrington Hills among them —
extend across county lines, so the population figures below are citywide, not Kane County-only
shares. CDP stands for census designated place; Unincorp. covers hamlets and rural crossroads
with no formal boundary.

Four places straddle county lines and their table figures are citywide, not Kane-only shares.
Bartlett and Hoffman Estates sit mostly in Cook and DuPage counties, with only a slice of each
reaching into Kane. Barrington Hills spans Cook, Lake, McHenry and Kane counties, and Aurora
itself extends into DuPage, Kendall and Will counties — its 180,542 residents are not all
Kane County residents. Township is left blank above where a place incorporates across more than
one township or the township line runs through it.

ZIP Codes

• 60502–60507 — Aurora (also 60568, 60569, 60572 and 60598, which are PO box or
  business-only ZIPs)
• 60120, 60121, 60123, 60124 — Elgin
• 60174, 60175 — St. Charles
• 60510 — Batavia (also 60539, a Batavia PO box ZIP)
• 60134 — Geneva
• 60110 — Carpentersville
• 60102 — Algonquin
• 60542 — North Aurora
• 60554 — Sugar Grove

The county’s smaller villages — Kaneville, Virgil, Big Rock, Lily Lake, Maple Park
and Burlington among them — are served by ZIP codes centred on a neighboring post office
rather than one of their own; this page lists only the ZIPs verified against each place’s own
postal designation.

Geography

Kane County lies in Illinois’s Fox River Valley, part of the state’s northeastern
till plain left behind by the last glaciation — mostly flat to gently rolling farmland and
suburb, with almost no relief. Of its 524 square miles, about 520 are land and 4.1 are water, just
under 1 percent, carried mainly by the Fox River, which runs the length of the county
north-to-south through Elgin, South Elgin, St. Charles, Geneva, Batavia and Aurora, and by Fox
River-fed forest preserve lakes and ponds along its course.

McHenry County lies to the north, Cook County to the northeast, DuPage County to the east, Will
County to the southeast, Kendall County to the south, LaSalle County to the southwest, DeKalb
County to the west, and Boone County to the northwest. Cook County,
DuPage County,
Will County and
LaSalle County all have live pages on
this site; McHenry, Kendall, Boone and DeKalb counties do not yet, so they are listed here without
a link. DeKalb County has a page, but under a different Illinois-suffixed slug: DeKalb County.

Demographics

Kane County had a population of 516,522 at the 2020 census, the fifth-most populous county in
Illinois, and the latest estimate puts the county near 525,757 residents. Aurora and Elgin are by
far the two largest communities, together holding well over half the county’s population.
Median household income runs $103,163, well above Illinois’s statewide figure of $80,306
(2023 ACS). Population density works out to roughly 993 people per square mile of land, dense for
a county outside Chicago’s core, reflecting Kane’s place inside the
Chicago–Naperville–Elgin metropolitan area.

Economy & Local Life

Manufacturing employs the most workers in the county, about 41,298 people, followed by retail
trade at 30,612 and health care and social assistance at 30,497. Fermilab, the federal high-energy
physics laboratory just east of Batavia’s city limits, is where researchers first detected
the bottom and top quarks and remains a major regional employer and research draw. Aurora’s
largest employers include Rush Copley Medical Center, Caterpillar Inc. and the Hollywood Casino
Aurora riverboat casino; Elgin’s include Advocate Sherman Hospital, John B.
Sanfilippo/Fisher Nuts and the Grand Victoria Casino. St. Charles hosts the county’s biggest
annual event, the Scarecrow Festival, each October, drawing crowds to see more than 100 handmade
scarecrows displayed downtown.

History

Illinois organized Kane County on 16 January 1836, carving it from LaSalle County. It was named
for Elias Kane, Illinois’s first Secretary of State and a United States senator from
Illinois. Geneva was platted the same decade and became the county seat.

Swedish immigrants settled Geneva in large numbers through the late 1800s, and by 1900 they
made up roughly half the city’s population, a heritage still marked in the city’s
downtown. Batavia earned the nickname “the Windmill City” when six American-style
windmill manufacturers operated there in the late 19th century. Aurora, the county’s
largest city, was one of the first American cities to use an all-electric street lighting system,
earning it the nickname “the City of Lights.”

Getting There

Interstate 88, a toll road, crosses the county’s south side through Aurora, and Interstate
90 crosses the northeast corner near Elgin. US 20, US 30 and US 34 also run through the county.

• Chicago — about 40 miles east
• Rockford — about 45 miles northwest
• Joliet — about 25 miles southeast
• DeKalb — about 25 miles west

O’Hare International Airport, roughly 30 miles northeast of Aurora, is the nearest major
commercial airport. Aurora Municipal Airport in Sugar Grove handles general aviation. The county
has no Amtrak station; Metra commuter rail connects Aurora (BNSF Line), Elgin (Milwaukee District
West Line) and Geneva, St. Charles and Batavia (Union Pacific West Line) to Chicago Union
Station.

Frequently Asked Questions

Where is Kane County located?
It sits in Illinois’s Fox River Valley, about 40 miles west of downtown Chicago, bordered by
McHenry, Cook, DuPage, Will, Kendall, LaSalle, DeKalb and Boone counties.

What is the population of Kane County?
516,522 at the 2020 census, with a 2025 estimate near 525,757.

How big is Kane County?
524 square miles (1,357 km2), of which about 520 square miles are land.

What is the county seat of Kane County?
Geneva is the county seat; Aurora, largely within the county, is the largest city.

How many towns and cities are in Kane County?
30 incorporated cities and villages, plus the census-designated place of Prestbury.

What ZIP codes does Kane County use?
60502–60507 for Aurora, 60120–60124 for Elgin, 60174 and 60175 for St. Charles, 60510
for Batavia, 60134 for Geneva, plus 60110, 60102, 60542 and 60554 for Carpentersville, Algonquin,
North Aurora and Sugar Grove.

What is Kane County known for?
Fermilab, the federal particle physics laboratory near Batavia, and Aurora’s history as one
of the first American cities lit entirely by electric street lights.

More counties in this state: Towns and villages in Illinois.