The records we need vary greatly based on the type of tax you are required to pay. In general, we need access to records that support the line-by-line items reported on your tax returns. We may require your records only in samples or in detail. We may also require you to keep specific records that will help the Department decide if you have a liability for a given tax type. Additional requirements for record keeping, including electronic formats and record retention limitation agreements, may be found in our regulations. For sales tax issues, see
Illinois Administrative Code, Title 86, Sections 130.801 through 130.825. For income tax issues, see
Illinois Administrative Code, Title 86, Section 100.9530.