Illinois residents pay 21.63 percent of their wireless bill in state, local, and federal taxes and fees. The national average is 17.05 percent.  And wireless customers in Chicago with multiple lines on their cell phone plan pay an astonishing 35.4 percent of their bill to taxes and fees, the highest rate in the country.

http://blogs.pjstar.com/mindingbiz/2014/10/08/illinois-residents-pay-plenty-in-cell-phone-taxes/