U.S. Department of Housing and Urban Development 

https://www.hud.gov/

City of Chicago-Affordable Rental Housing Resource List

https://www.chicago.gov/city/en/depts/doh/provdrs/renters/svcs/affordable-rental-housing-resource-list.html

Community Action Agencies

https://www.iacaanet.org/

Rentervention

https://rentervention.com/

Illinois Housing Development Authority 

https://www.ihda.org/

The Chicago Housing Authority

https://www.thecha.org/

Map-based search for USDA affordable rental housing in rural areas

https://rdmfhrentals.sc.egov.usda.gov/RDMFHRentals/select_state.jsp 

Illinois Legal Aid

https://www.illinoislegalaid.org/legal-information/house-apartment

Illinois Housing Search

https://ilhousingsearch.org/

USDA Housing Programs Illinois (rural areas only)

https://www.rd.usda.gov/il

The Illinois Network of Centers for Independent Living (INCIL)

https://incil.org/

Metropolitan Tenants Organization

https://www.tenants-rights.org/