Rochester, Illinois Demographics & Population 2026
During the 2020–2024 ACS period, Rochester, Illinois had a total population of 3,766, the 391st largest village in Illinois, with a median household income of $117,118, which is 40% higher than the state average. The poverty rate is 2.5%.
Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes
Key Takeaways
- Household income is 40% above the state average — one of the wealthiest communities in Illinois.
- An exceptionally low poverty rate of 2.5% — among the lowest in Illinois.
- 47.9% of adults hold a bachelor's degree or higher — top 10% in Illinois.
- Housing is very affordable with a home-value-to-income ratio of just 2.0x.
Rochester Quick Facts
How Rochester Changed
Change from the 2019–2023 ACS period to 2020–2024. These are rolling five-year estimates, not year-over-year measurements.
| Metric | 2019–2023 | 2020–2024 | Change |
|---|---|---|---|
| Population | 3,784 | 3,766 | -0.5% |
| Median household income | $112,689 | $117,118 | +3.9% |
| Median home value | $241,900 | $238,900 | -1.2% |
How Rochester Compares
Median Household Income
Median Home Value
Economy & Housing
Household Income Distribution
Detailed income brackets
Employment
Housing Overview
People & Demographics
Age Distribution
Race & Ethnicity
Diversity Index
A less diverse community where one racial or ethnic group represents a large majority.
State average: 61 | National average: 61
Education
Educational Attainment (Adults 25+)
Rochester Rankings in Illinois
Explore Illinois Rankings
Other Cities in Sangamon County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| Springfield | 113,330 | $66,064 | 16.8% | $162,100 |
| Chatham | 14,639 | $106,773 | 3.3% | $243,200 |
| Sherman | 4,386 | $148,906 | 2.2% | $297,800 |
| Auburn | 4,306 | $81,411 | 8.1% | $149,600 |
| Riverton | 3,513 | $80,920 | 0.9% | $152,200 |
| Virden | 3,171 | $80,577 | 10.2% | $101,300 |
| Pawnee | 2,738 | $81,103 | 14.2% | $149,500 |
| Jerome | 1,807 | $65,189 | 6.4% | $127,800 |
| Southern View | 1,751 | $57,270 | 14.9% | $105,300 |
| Leland Grove | 1,517 | $130,833 | 2.9% | $274,300 |
Cities Similar to Rochester
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| St. Joseph | 3,778 | $120,789 | $270,900 | 35.3% | 4.1% |
| Poplar Grove | 3,923 | $120,278 | $270,700 | 31.1% | 3.7% |
| Forsyth | 3,502 | $112,000 | $281,000 | 59.3% | 11.3% |
| Smithton | 3,680 | $135,455 | $256,300 | 40.6% | 3.4% |
| Scott AFB | 3,957 | $103,390 | N/A | 33.8% | 5.7% |
Population Overview
Rochester is a small community located in Illinois, within Sangamon County. The total population is 3,766. It ranks as the 391st most populous out of 1,445 Census-designated places in Illinois.
Age Demographics
The median age in Rochester is 39.8 years. This is 2% higher than the state median of 39.0 years.
Economy, Income & Housing
The median household income in Rochester is $117,118. This is 40% higher than the state median of $83,390. It is also 45% higher than the national median of $80,734. The poverty rate stands at 2.5%. This is 79% lower than the state poverty rate of 11.8%. This exceptionally low poverty rate indicates strong economic prosperity across the community. The unemployment rate is 2.9%. This is 50% lower than the state rate of 5.8%. The median home value is $238,900. Housing costs are 9% lower than the state median of $263,300. With a home-value-to-income ratio of just 2.0x, Rochester is one of the most affordable housing markets in the area. 93.3% of occupied housing units are owner-occupied. This homeownership rate is 39% higher than the state average of 67.1%.
Race & Ethnicity
Rochester has a predominantly White (non-Hispanic) population, comprising 91.6% of all residents. Asian residents account for 2.1%. The White (non-Hispanic) population is significantly higher than the state average (91.6% vs 58.1%). The Black or African American population (1.5%) is well below the state average of 13.3%. The Hispanic or Latino population (1.0%) is well below the state average of 18.8%. The Asian population (2.1%) is well below the state average of 5.9%.
Education
47.9% of residents aged 25 and older hold a bachelor's degree or higher. This places Rochester in the top 10% of all cities in the state for educational attainment. This is 27% higher than the state rate of 37.9%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 98.6%. Notably, 16.7% of adults hold a graduate or professional degree, indicating a highly educated workforce.
Data Sources & Methodology
All demographic data for Rochester, Illinois is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Illinois state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,445 Census-designated places in Illinois. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.
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Frequently Asked Questions
What is the population of Rochester, Illinois?
Rochester, Illinois has a population of 3,766 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in Rochester, IL?
The median household income in Rochester is $117,118, which is 45% higher than the national median of $80,734.
What is the poverty rate in Rochester, IL?
The poverty rate in Rochester is 2.5%. This means approximately 94 residents live below the federal poverty line.
What is the racial makeup of Rochester, Illinois?
Rochester's population is 91.6% White, 1.5% Black, 1.0% Hispanic/Latino, and 2.1% Asian.
What is the median home value in Rochester, IL?
The median home value in Rochester is $238,900. The home-value-to-income ratio is 2.0x.
How educated is Rochester, Illinois?
47.9% of adults (25+) in Rochester hold a bachelor's degree or higher, and 16.7% hold a graduate or professional degree.