Section 20 ILCS 2510/2510-20 - Notification(a) A qualified practitioner shall notify the Department of an engagement to perform a certified audit and shall provide the Department with the information the Department deems necessary to identify the taxpayer, to confirm that the taxpayer is not already under audit by the Department, and to establish the basic nature of the taxpayer's business and the taxpayer's potential exposure to Illinois occupation and use tax laws. The information provided in the notification shall include the taxpayer's name, federal employer identification number or social security number, Illinois business tax number, mailing address, business location, and the specific occupation and use taxes and period proposed to be covered by the engagement for the certified audit. In addition, the notice shall include the name, address, identification number, contact person, and telephone number of the engaged firm.(b) If the taxpayer has not been issued a written notice of intent to conduct an audit, the taxpayer shall be a participating taxpayer and the Department shall so advise the qualified practitioner in writing within 10 days after receipt of the engagement notice. However, the Department may exclude a taxpayer from a certified audit or may limit the taxes or periods subject to the certified audit on the basis that the Department has previously conducted an audit, that it is in the process of conducting an investigation or other examination of the taxpayer's records, or for just cause.(c) Notice of the qualification of a taxpayer for a certified audit shall toll the statute of limitations provided with respect to the taxpayer for the tax and periods covered by the engagement.(d) Within 30 days after receipt of the notice of qualification from the Department, the qualified practitioner shall contact the Department and submit a proposed audit plan and procedures for review and agreement by the Department. The Department may extend the time for submission of the plan and procedures for reasonable cause. The qualified practitioner shall initiate action to advise the Department that amendment or modification of the plan and procedures is necessary in the event that the qualified practitioner's inspection reveals that the taxpayer's circumstances or exposure to the revenue laws is substantially different than as described in the engagement notice. P.A. 92-456, eff. 8/21/2001.