| Official Name: | Riley, Illinois |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Illinois#USA |
| Pushpin Label: | Riley |
| 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: | Riley |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 0.46 |
| Area Land Km2: | 0.46 |
| Area Water Km2: | 0.00 |
| Area Total Sq Mi: | 0.18 |
| Area Land Sq Mi: | 0.18 |
| Area Water Sq Mi: | 0.00 |
| Population As Of: | 2020 |
| Population Total: | 10 |
| Population Density Km2: | 21.80 |
| Population Density Sq Mi: | 56.50 |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 807 |
| Coordinates: | 42.1914°N -88.6325°W |
| Area Code: | 815 & 779 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 423120 |
Riley, elevation, is an unincorporated community and census-designated place in McHenry County, Illinois, United States. It was named a CDP before the 2020 census, at which time it had a population of 10.[2]
The community is located on the north side of the junction of Anthony Road, which runs east–west and Riley Road, which runs north–south. Both of these are Riley Township highways. In terms of geographic coordinates, the community is located at 42.1914°N -88.6325°W (42.1914123, -88.6325924).[3] In terms of the Public Land Survey System, Riley is found in the Northeast Quarter of Section 22, Township 43 North, Range 5 East of the Third Principal Meridian. The main branch of Coon Creek flows to the west of the community in a generally southeast to northwest direction, and a minor branch of the same creek flows from east to west to the north of the community.[4] Riley is served by the Marengo, Illinois 60152 post office.
Riley first appeared as a census designated place in the 2020 U.S. Census.[5]
| White alone (NH) | 8 | 80.00% | |
| Black or African American alone (NH) | 0 | 0.00% | |
| Native American or Alaska Native alone (NH) | 0 | 0.00% | |
| Asian alone (NH) | 0 | 0.00% | |
| Pacific Islander alone (NH) | 0 | 0.00% | |
| Other race alone (NH) | 0 | 0.00% | |
| Mixed race or Multiracial (NH) | 1 | 10.00% | |
| Hispanic or Latino (any race) | 1 | 10.00% | |
| Total | 10 | 100.00% |
Riley Community Consolidated (K-8) School, District #18, 9406 Riley Road;[7] the Riley Center Memorial Cemetery; old Riley Township Hall; and the Riley Township War Memorial.