You can mail the completed application for search of death record files, PDF format, (Click here if you're having trouble downloading the form.) and a check or money order (Do not send cash)for the required fee made payable to the "Illinois Department of Public Health" to:

Illinois Department of Public Health
Division of Vital Records
925 East Ridgely Ave.
Springfield, IL 62702-2737

Regular mail requests, on average, are processed in 4 to 6 weeks. (Please note: this does not include mail delivery time to and from this office.)