820 ILCS 405/1508
The Director shall periodically furnish each employer with a statement of the wages of his workers or former workers which became his benefit wages together with the names of such workers or former workers. The Director shall also periodically furnish each employer with a statement of benefits which became benefit charges together with the names of such workers or former workers. Any such statement, in absence of an application for revision thereof within 45 days from the date of mailing of such statement to his last known address, shall be conclusive and final upon the employer for all purposes and in all proceedings whatsoever. Such application for revision shall be in the form and manner prescribed by regulation of the Director. If the Director shall deem any application for revision insufficient, he shall rule such insufficient application stricken and shall serve notice of such ruling and the basis therefor upon the employer. Such ruling shall be final and conclusive upon the employer unless he shall file a sufficient application for revision within 20 days from the date of service of notice of such ruling. Upon receipt of a sufficient application for revision of such statement within the time allowed, the Director shall order such application allowed in whole or in part or shall order that such application for revision be denied and shall serve notice upon the employer of such order. Such order of the Director shall be final and conclusive at the expiration of 20 days from the date of service of such notice unless the employer shall have filed with the Director a written protest and a petition for hearing, specifying his objections thereto. Upon receipt of such petition within the 20 days allowed, the Director shall fix the time and place for a hearing and shall notify the employer thereof. At any hearing held as herein provided, the order of the Director shall be prima facie correct and the burden shall be upon the protesting employer to prove that it is incorrect. All of the provisions of this Act, applicable to hearings conducted pursuant to Section 2200 and not inconsistent with the provisions of this Section, shall be applicable to hearings conducted pursuant to this Section. No employer shall have the right to object to the benefit wages or benefit charges with respect to any worker as shown on such statement unless he shall first show that such benefit wages or benefit charges arose as a result of benefits paid to such worker in accordance with a finding, reconsidered finding, determination, or reconsidered determination, or for 1987 or any calendar year thereafter a Referee's decision, to which such employer was a party entitled to notice thereof, as provided by Sections 701 to 703, inclusive, or Section 800, and shall further show that he was not notified of such finding, reconsidered finding, determination, or reconsidered determination, or for 1987 or any calendar year thereafter such Referee's decision, in accordance with the requirements of Sections 701 to 703, inclusive, or Section 800. Nothing herein contained shall abridge the right of any employer at such hearing to object to such statement of benefit wages or statement of benefit charges on the ground that it is incorrect by reason of a clerical error made by the Director or any of his employees. The employer shall be promptly notified, by mail, of the Director's decision. Such decision shall be final and conclusive unless review is had within the time and in the manner provided by Section 2205.
820 ILCS 405/1508