820 ILCS 405/2200
If it shall appear to the Director that any employing unit or person has failed to pay any contribution, interest or penalty as and when required by the provisions of this Act or by any rule or regulation of the Director, or if the amount of any contribution payment made by an employing unit for any period is deemed by the Director to be incorrect in that it does not include all contributions payable for such period, or if the Director shall find that the collection of any contributions which have accrued but are not yet due will be jeopardized by delay, and declares said contributions immediately due and payable, or if it shall appear to the Director that he has made any final assessment which did not include all contributions payable by the employer for the periods involved, or if it appears to the Director that any employing unit or person has, by reason of any act or omission or by operation of law, become liable for the payment of any contributions, interest or penalties not originally incurred by him, the Director may in any of the above events determine and assess the amount of such contributions or deficiency, as the case may be, together with interest and penalties due and unpaid, and immediately serve notice upon such employing unit or person of such determination and assessment and make a demand for payment of the assessed contribution together with interest and penalties thereon. If the employing unit or person incurring any such liability has died, such assessment may at the discretion of the Director be made against his personal representative. Such determination and assessment by the Director shall be final at the expiration of 20 days from the date of the service of such written notice thereof and demand for payment, unless such employing unit or person shall have filed with the Director a written protest and a petition for a hearing, specifying its objections thereto. Upon the receipt of such petition within the 20 days allowed, the Director shall fix the time and place for a hearing and shall notify the petitioner thereof. The Director may amend his determination and assessment at any time before it becomes final. In the event of such amendment the employing unit or person affected shall be given notice thereof and an opportunity to be heard in connection therewith. At any hearing held as herein provided, the determination and assessment that has been made by the Director shall be prima facie correct and the burden shall be upon the protesting employing unit or person to prove that it is incorrect. Upon the conclusion of such hearing a decision shall be made by the Director either canceling, increasing, modifying or affirming such determination or assessment and notice thereof given to the petitioner. Such notice shall contain a statement by the Director of the cost of the certification of the record computed at the rate of 5 per 100 words. The record shall consist of the notices and demands caused to be served by the Director, the original determination and assessment of the Director, the written protest and petition for hearing, the testimony introduced at such hearing, the exhibits produced at such hearing, or certified copies thereof, the decisions of the Director and such other documents in the nature of pleadings filed in the proceeding.
820 ILCS 405/2200