An overview of the general cost of living index for Downers Grove, IL is displayed above for your reference. Residents in Downers Grove, IL enjoy a cost of living index of 119. This index is 21% higher than the Illinois average, and 19% higher than the national average. The following categories are used when determining the cost of living index for any given city: health care (5%), transportation (9%), utilities (10%), groceries (13%), housing (30%), and goods/services (33%). Clearly, housing and goods/services make up the majority of the formula for calculating the cost of living index. Because of this, the general cost of living for any given area can be estimated by looking at the cost of everyday goods in that area. For those living in Downers Grove, IL, the average cost of goods and services is equal to it is in Illinois, and it is 2% lower than the national average.