Montgomery County, Illinois

County seat: Hillsboro · Population 28,076 (2025) · 704 sq mi

Montgomery County is the 48th most populous of Illinois's 102 counties, with 28,076 people (2025 estimate). Its county seat is Hillsboro. It is part of the Central region, one of the 10 Illinois economic development regions (DCEO). The map shows its 20 cities and towns and the 7 neighboring counties.

Map of Montgomery County, Illinois with cities, towns and the county boundary
Montgomery County, Illinois with its cities and towns, unincorporated communities (CDPs) and neighboring counties. Boundaries: U.S. Census Bureau, 2025. Free to use with attribution (CC BY 4.0).
Download PDF (Letter) 112 KBPNG image 80 KBIllinois county map

Montgomery County facts

County seat
Hillsboro
Population (2025 estimate)
28,076 −0.9% since 2020
Land area
704 sq mi 25th largest of 102
Water area
6 sq mi
Population density
40 per sq mi
Established
1821
Same name
One of 18 Montgomery Counties in the US
Named after
Richard Montgomery Irish-born soldier in the British Army, later in the American Continental Army (1738–1775)
Largest city
Litchfield 6,598
Median household income
$63,620
Cities and towns
20
ZIP codes
28
Time zone
Central
FIPS code
17135

Cities and towns in Montgomery County

Montgomery County has 20 incorporated cities, towns and villages. Populations count the people living inside Montgomery County; cities that cross a county line also list the other counties.

NameTypePopulation 2025Also in
LitchfieldCity6,598
Hillsboro (county seat)City6,184
NokomisCity2,133
RaymondVillage920
WittCity770
Taylor SpringsVillage727
FarmersvilleVillage668
CoffeenCity627
Schram CityVillage555
IrvingVillage365
CoaltonVillage302
FillmoreVillage295
PanamaVillage205Bond County
WaggonerVillage180
ButlerVillage165
DonnellsonVillage145Bond County
HarvelVillage117Christian County
OhlmanVillage107
WalshvilleVillage63
WenonahVillage28

ZIP codes in Montgomery County

28 ZIP codes reach into Montgomery County. ZIP codes ignore county lines, so some also cover a neighboring county.

Population of Montgomery County, 2020–2025

Montgomery County shrank by 251 people (−0.9%) between April 2020 and July 2025: 681 more deaths than births and a net gain of 446 people from migration.

Year (July 1)Population
202028,244
202128,128
202227,958
202327,791
202427,837
202528,076

Neighboring counties

Printable Montgomery County map

The PDF is a vector file with real text: it prints sharp on Letter paper and you can search it for a town. The PNG is 2400 pixels wide for slides and documents. Both are free to use with a credit to WhichCounty.

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Sources

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