Audit Manual

​The public version of the Audit Manual has been redacted to remove certain material that is protected from disclosure under the Illinois Freedom of Information Act (5 ILCS 140/7). Redactions include tolerances or specialized audit techniques, or confidential or proprietary information. The public version of the Audit Manual is being provided for informational purposes only and shall not constitute written advice or guidance to taxpayers for any purpose, including, but not limited to, the Taxpayers' Bill of Rights. Highlighted text indicates the most recent revisions from the previous version. Audit manual updates will be incorporated into the chapters during the next revision.

• Income Tax Audit Manual
  
  • Income Tax Audit Manual Updates
    
• Sales Tax Audit Manual
  
• Miscellaneous Tax Audit Manual - will be added at a later date