The Town FilesSouth Wilmington, Illinois
Village in Grundy County · population 710 (2020 Census)
- Median home
- $174,400
- Household income
- $86,750
- Jan low / Jul high
- 14° / 84°
- Snow a year
- 23 in
- Tornadoes ≤10 mi since 1950
- 22
- Median age
- 43.0
South Wilmington is a village of 710 people in Grundy County, Illinois. The median home is worth $174,400, above the typical Illinois town ($156,600). It ranks easier by car than 99% of Illinois towns, better for cycling than 73% of Illinois towns.
How South Wilmington ranks
Percentile among Illinois towns with at least 500 people on The Town Files lifestyle rankings. 50 is typical for the state; 90 means better than 90% of Illinois towns.
Homes and cost of living
The median home in South Wilmington is worth $174,400, above the typical Illinois town ($156,600). Homes cost about 2.0 times the median household income of $86,750, which is more affordable than 61% of Illinois towns. Median rent is $1,277 a month. 90.0% of households own their home.
| Housing | South Wilmington | Typical Illinois town |
|---|---|---|
| Median home value | $174,400 | $156,600 |
| Median rent | $1,277 | $960 |
| Median household income | $86,750 | $72,500 |
| Home value ÷ income | 2.0× | 2.2× |
| Homeownership | 90.0% | 76.6% |
| Median year built | 1959 | 1967 |
| Seasonal / vacation homes | 0.0% | — |
Who lives in South Wilmington
| People | South Wilmington | Typical Illinois town |
|---|---|---|
| Median age | 43.0 | 40.4 |
| Age 65 and over | 18.5% | 18.7% |
| Under 18 | 20.2% | — |
| Bachelor's degree or higher | 13.1% | 21.8% |
| Below the poverty line | 5.7% | 9.9% |
| Veterans | 6.1% | — |
| Born outside the U.S. | 2.7% | — |
| Work from home | 3.8% | 8.9% |
| Average commute | 31.9 min | 26.1 min |
| Homes with broadband | 88.1% | 90.4% |
Weather in South Wilmington
July highs average 83.5°F and January lows 14.0°F. About 37.7 inches of rain and melted snow fall a year, with 23.3 inches of snow (typical Illinois town: 24.2 in). Expect about 16 days a year at 90°F or hotter and 140 nights at or below freezing.
Tornadoes, storms and disasters
22 tornadoes have passed within 10 miles of South Wilmington since 1950, compared with 27 for the typical Illinois town. 12 rated (E)F2 or stronger. The strongest, an F4, struck on April 17, 1963 about 9.3 miles from the town center and killed 1. Tornadoes within 10 miles have caused 2 deaths and 76 injuries since 1950. The most recent was on June 11, 2026.
Hail of 1 inch or larger has been reported within 10 miles 33 times; the largest was 5.00 inches on March 10, 2026.
Severe weather in Grundy County since 1996
Grundy County has been included in 15 federal disaster or emergency declarations since 1953, most often for flood, tornado, hurricane.
| Declared | Incident | Declaration |
|---|---|---|
| March 26, 2020 | Biological | DR-4489: Covid-19 Pandemic |
| March 13, 2020 | Biological | EM-3435: Covid-19 |
| November 26, 2013 | Tornado | DR-4157: Severe Storms, Straight-Line Winds, And Tornadoes |
| May 10, 2013 | Flood | DR-4116: Severe Storms, Straight-Line Winds, And Flooding |
| March 17, 2011 | Snowstorm | DR-1960: Severe Winter Storm And Snowstorm |
Jobs and pay in Grundy County
Grundy County had 22,349 jobs in 2024, paying an average of $69,868 a year. Unemployment was 4.6% in 2023; in South Wilmington itself the ACS puts it at 4.1%.
Public schools in South Wilmington
1 public school with 86 students, about 10.8 students per teacher.
| School | Grades | Students | Per teacher |
|---|---|---|---|
| South Wilmington Grade School | K-8 | 86 | 10.8 |
Towns near South Wilmington
- Gardner, IL2.2 mi · 1,366 people · home $199,600
- Braceville, IL3.6 mi · 724 people · home $187,900
- Essex, IL4.6 mi · 841 people · home $228,200
- Godley, IL5.2 mi · 566 people · home $144,600
- Coal City, IL7.2 mi · 5,705 people · home $201,600
- Braidwood, IL7.2 mi · 6,194 people · home $202,500
- Diamond, IL7.8 mi · 2,640 people · home $220,200
- Mazon, IL8.8 mi · 979 people · home $207,700
South Wilmington questions
Is South Wilmington, Illinois a good place to retire?
On The Town Files lifestyle rankings, South Wilmington scores better for retirees than 23% of Illinois towns and quieter than 59%. 18.5% of residents are 65 or older (median age 43.0).
How much does a house cost in South Wilmington?
The median owner-occupied home in South Wilmington is valued at $174,400 (Census ACS 2020–2024), against a median household income of $86,750, so homes cost about 2.0 times income. Median rent is $1,277 a month.
What is the weather like in South Wilmington?
July highs average 83.5°F and January lows 14.0°F (NOAA 1991–2020 normals). It gets about 37.7 inches of precipitation a year and 23.3 inches of snow.
Does South Wilmington get tornadoes?
22 tornadoes have passed within 10 miles of South Wilmington since 1950 (NOAA Storm Events); the strongest was a F4 on April 17, 1963. The typical Illinois town has had 27.
- U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024)
- U.S. Census Bureau, 2020 Census and 2025 Gazetteer (2020 / 2025)
- NOAA NCEI U.S. Climate Normals (1991–2020)
- NOAA NCEI Storm Events Database (1950–2026)
- FEMA OpenFEMA Disaster Declarations (this product uses the FEMA OpenFEMA API but is not endorsed by FEMA) (1953–2026)
- NCES Common Core of Data (2023–24)
- BLS Quarterly Census of Employment and Wages; USDA ERS county unemployment (BLS LAUS) (2000–2024)
- The Town Files lifestyle rankings, built from federal demographic, school, crime and housing data (2025)