The City of Chicago has approved and adopted an amended and restated City of Chicago Deferred Compensation. Beneficiary Information.If you would like to confirm or update your beneficiary information, please visit our website at ChicagoDeferredComp. Download any State of Illinois Deferred Compensation Plan form now using Acrobat Reader. These forms allow data to be typed into the form and saved. A deferred compensation agreement is an agreement between a company and an employee that withholds paying some of the employee's salary. You defer a portion of your eligible compensation, up to IRS limits for the 457(b) Deferred Compensation Plan, on a pre-tax basis. The State of Illinois Deferred Compensation Plan is a supplemental retirement program for State employees.