Ill. Admin. Code tit. 86 § 130.1605
However, if such taxpayer has been duly granted permission by the Department, and has consistently used gross amount of sales as the method of computing his liability for tax under the Act, he will not be required to continue to file returns or to pay any tax after selling out or discontinuing his business except for the final return which would be due from him in any event under Section 130.520 of this Part for the last reporting period in which he did operate his business, but, in this event, he must file with the Department a Certificate of Discontinuation of Business. Since such taxpayer has filed returns and paid tax with respect to all sales made by him at the time when such sales were made, he does not receive any further receipts which are subject to the Retailers' Occupation Tax.
Ill. Admin. Code tit. 86, § 130.1605
Amended and effective April 8, 1963