Troy, Illinois

How many people live in Troy?

The latest official estimate is 11,893 residents on July 1, 2025. It ranks 2,846th by population nationally and 201st in Illinois among this directory’s PEP places. Population changed by 86 residents between the 2024 and 2025 estimates. These are annual estimates, not census enumerations.

From the revised April 2020 base to July 2025, the change is +465 residents (4.1%). This is a within-vintage comparison. Boundary adjustments can affect both the estimates and their interpretation.

Download this population chart (SVG) · Official population release

Where are the boundaries?

Entity and stable identifier

Troy city, Illinois · Incorporated city · 1776199

Counties or equivalents · 2025 boundaries

Madison County

Metropolitan or micropolitan context · July 2023 delineations

St. Louis, MO-IL — Metropolitan Statistical Area County associations use Census PEP county place parts. Each county is matched by FIPS code to the official CBSA list; a city can span several counties or statistical areas. A missing association can reflect an area outside a CBSA or changed county codes between vintages. City figures on this page remain place-level statistics.

Land area

6.2 square miles · 2025 Gazetteer

Water area

0.1 square miles · 2025 Gazetteer

Approximate population density

1,906 residents per square mile of land

Internal point

38.726219°, -89.89347° · Census geographic reference point

Density divides the July 2025 estimate by 2025 Gazetteer land area, so it is approximate. The internal point is a locator, not an address. Census place profile reference .

Income and poverty

Household income combines the incomes of everyone in a household; per-capita income divides all income by every resident. The poverty rate is 2.0% (±1.1 percentage points · low precision) under the official Census definition.

Home values, rent and tenure

Owner-occupied units make up 73.6% of occupied housing. Gross rent includes estimated tenant-paid utilities and home values are owners’ own estimates; both cover 2020–2024 leases and homes rather than current listings. The median home value is 2.4 times the median household income.

See housing units, occupancy, rent burden and homeowner costs .

Monthly rent by bedroom count

Census table B25031 describes renter-occupied units paying cash rent within this exact place geography. Gross rent includes contract rent and estimated tenant-paid utilities. These survey medians include existing leases across 2020–2024; they are not current apartment listings. Missing categories stay unavailable, and open-ended medians remain ranges. Small bedroom categories can have large margins of error. Download source values and provenance .

Employment among residents

These estimates describe residents of Troy wherever they work; jobs at workplaces inside the city appear under jobs located in Troy. They are 2020–2024 averages, not a current monthly unemployment rate.

Which industries employ residents?

Education, health care and social assistance is the largest of the published broad industry groups among employed residents: 28.7% (1,696 people; ±4.9 percentage points). The estimate covers residents’ industries wherever they work, rather than employers located inside the place.

Occupations among employed residents

The detailed groups are subsets of the broad groups and should not be added to them.

How residents get to work

Travel times cover workers who did not work from home. Vehicle availability is counted per household, not per driver.

Households and residents

Median age is 35.2 years (±1.8). The demographic profile covers age groups, race and Hispanic origin, household types, nativity, languages, education and moves, each compared with Illinois and the U.S.

Read Troy demographics →

How many jobs are located in Troy?

Employers in Troy reported 3,007 jobs in 2023, +7.3% compared with 2019 (2,803 jobs). That is 25.7 jobs for every 100 residents in the July 2023 population estimate. These are jobs at workplaces inside the city limits, wherever the workers live, unlike resident employment figures.

Educational services is the largest sector for jobs located in Troy (23.6% of local jobs, compared with 9.5% statewide). Earnings bands describe what each job pays per month, not household income, and a worker can hold more than one job.

Source: Census LEHD Origin-Destination Employment Statistics (LODES) 8.4, workplace area characteristics, all jobs, second-quarter reference date. Census blocks are summed to 2024 place boundaries. Includes private, state and local government and federal civilian jobs; excludes self-employment, military and informal work. Counts include confidentiality noise and are less precise for small places.

Nearby station climate normals

BELLEVILLE SIU RSCH, IL (NOAA station USW00013802) is approximately 23.3 km from this place’s Census internal point. The table describes that station’s 1991–2020 climate normals, using NOAA’s corrected version 1.0.1. It is historical station context, rather than a forecast or an average across the city.

Station location: 38.52°, -89.8467°; elevation 137.2 meters. We select the nearest station within 25 km with all 12 months of high/low temperature and precipitation marked “S” (standard) by NOAA. Standard normals meet NOAA’s data-availability rules and can include estimated missing months. Distance is a straight-line great-circle calculation from the Census internal point. Coastal exposure, elevation and urban conditions can differ between the station and an address. NOAA normals and definitions · Original station CSV · Retained station data, flags and matching details .

Check a specific address before moving

City averages help compare places. A particular home’s school assignment, transit service and flood-map coverage need checks at the address.

• FEMA Flood Map Service Center — search the address, read the effective map and its date, and check any map changes. An unmapped location does not establish an absence of flood risk.
• NCES public school district directory — find district contact information, then use the district’s official address locator or enrollment office to confirm school assignment. A city name or district boundary alone does not assign a school.
• FCC National Broadband Map — check reported service at the exact location, then confirm availability and terms with the provider.
• Check the official transit operator’s route map and timetable for the address and your actual travel hours; the citywide commuting shares above do not measure service on a particular street.

Cities and towns near Troy

The nearest covered place is Maryville, IL, about 3.9 miles west. 10 places within 11 miles are listed below. Distances are straight lines between Census internal points, not road distances or boundary gaps.

Compare Troy with its 3 nearest places

Largest places in the St. Louis, MO-IL metropolitan area

Troy is the number 44 of 272 covered places with land in the counties that make up this area. Together these places hold 1,968,567 residents; unincorporated areas are not included in this sum.

• St. Louis 278,144
• O'Fallon 96,101
• St. Charles 72,561
• St. Peters 61,479
• Florissant 51,124
• Wentzville 49,495
• Chesterfield 49,309
• Belleville 40,237

Places elsewhere with a similar statistical profile

These places have half to twice Troy’s population and the closest reliable estimates for household income, home value, rent, median age, bachelor’s degrees, homeownership and density. Places within 60 miles are excluded. The match describes Census measures, not climate, amenities or character.

Compare Troy with its three closest lookalikes · How lookalikes are chosen

Sources and data notes

Population: Census PEP Vintage 2025, published May 14, 2026. Survey measures: ACS 2020–2024 five-year estimates, published January 29, 2026, dollar figures in 2024 dollars. Geography: Census 2025 Gazetteer, with simplified 2024 state outlines for the locator. Statistical estimates and derived values use the same retained records in profiles, comparison, filters and downloads.

Climate uses NOAA 1991–2020 station normals (v1.0.1); jobs located in the city use LEHD LODES 8.4. Crime, school assignments and hazard scores are not inferred from these datasets, and missing values are never treated as zero. Inspect original sources, read calculation details, download this place’s source observations , or submit a correction.