As of December 3, 2003, the following thirty-nine out of Illinois' 102 counties are under the provisions of this law: Boone, Champaign, Christian, Coles, Cook, Cumberland, DeKalb, DuPage, Franklin, Greene, Jackson, Jefferson, JoDaviess, Kane, Kankakee, Kendall, Lake, Lee, Livingston, Logan, Macoupin, Marion, Massac, McDonough, McHenry, Menard, Monroe, Morgan, Randolph, Sangamon, Schuyler, Shelby, Stephenson, Tazewell, Union, Washington, Will, Williamson, and Winnebago.

(PTELL Referendum was rejected in: Adams (April 1997); Bureau (March 1998); Carroll (Nov. 1997); Edgar (April 2001); LaSalle (Nov. 1997); Madison (April 1999); McLean (April 1997); Moultrie (April 2003); Shelby (April 1997, later passed in Nov. 2000); Whiteside (Nov. 1997); and Massac (Nov. 1996, later passed in Nov. 2000).

The tax caps restrict the ability to levy higher taxes by all local governments in a tax capped county except home rule units. Under the 1970 Illinois Constitution, home rule units are the County of Cook, all municipalities with a population over 25,000, and any other municipality if home rule is approved by a voter referendum. In addition, four communities voted to rescind their home rule status -- Lisle, Lombard, Rockford, and Villa Park -- and are under tax caps. Illinois has over 6,000 units of local government, the vast majority of which are non-home rule and therefore limited by the caps if they are located in a tax capped county.

While many public officials now realize that tax caps have adversely affected the ability of local governments to provide basic services, the law is still very popular. Former Governor Jim Edgar and many legislators believe that tax caps were their most important accomplishment. It is unlikely that tax caps will ever be repealed. In the last several years, however, there have been a few small modifications to the law which have permitted some local governments to levy higher taxes for selected purposes without referendum.