State Summary
Illinois is a lien state. Tax sales are the responsibility of the county treasurer. State law requires that bidders be registered at least 10 business days prior to the start of the sale. Different counties have different requirements for registration and for payment. Some counties will require that you put up some form of deposit in order to bid and some counties will only accept certified funds in the exact amount owed (no cash). By law, the maximum interest rate bid is 18% per 6 months, that’s 36% per year. Illinois pays the highest interest rate of all the tax lien states, but the interest rate is bid down at the tax sale.
According to information from the DuPage County treasurer’s website: in the last several years the average successful bids ranged from 0% to 3%
The redemption period is 2 – 2 1/2 years depending on the classification of the property. If the tax lien is not redeemed by the owner, the purchaser must petition the circuit court for a tax deed, after first fulfilling all of the legal requirements. The lien holder may also pay all subsequent taxes at a specified time and record the payments against the sale.
Although you can find tax sale information online for a few counties, only the larger counties will have property lists online. Cook County had its first online tax sale in December of 2009.
Summary courtesy of Joanne Musa's
State Guide