| Official Name: | Solon Mills, Illinois |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Illinois#USA |
| Pushpin Label: | Solon Mills |
| Pushpin Label Position: | bottom |
| Subdivision Type: | Country |
| Subdivision Name: |  United States |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | McHenry |
| Subdivision Type3: | Township |
| Subdivision Name3: | Richmond |
| Leader Title: | Sheriff |
| Leader Name: | Mike Lynn |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 0.50 |
| Area Land Km2: | 0.50 |
| Area Water Km2: | 0.00 |
| Area Total Sq Mi: | 0.20 |
| Area Land Sq Mi: | 0.20 |
| Area Water Sq Mi: | 0.00 |
| Population As Of: | 2020 |
| Population Total: | 133 |
| Population Density Km2: | 263.51 |
| Population Density Sq Mi: | 682.05 |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 771 |
| Coordinates: | 42.4422°N -88.2733°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 60071, 60080 (former) |
| Area Code: | 815 & 779 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 418701[2] |
Solon Mills is an unincorporated community and census-designated place in McHenry County, Illinois, United States. Solon Mills is located on U.S. Route 12, 2miles southwest of Spring Grove. Solon Mills is part of ZIP code 60071; it once had its own post office with ZIP code 60080 before it closed on September 28, 2002.[3] [4] It was named a CDP before the 2020 census, at which time it had a population of 133.[5]
Solon Mills, Illinois first appeared as a census designated place in the 2020 U.S. Census.
| White alone (NH) | 111 | 83.46% | |
| Black or African American alone (NH) | 0 | 0.00% | |
| Native American or Alaska Native alone (NH) | 1 | 0.75% | |
| Asian alone (NH) | 0 | 0.00% | |
| Pacific Islander alone (NH) | 0 | 0.00% | |
| Some Other Race alone (NH) | 0 | 0.00% | |
| Mixed Race or Multi-Racial (NH) | 10 | 7.52% | |
| Hispanic or Latino (any race) | 11 | 8.27% | |
| Total | 133 | 100.00% |