Applying for a City of Chicago Business License. Every business operating in the City of Chicago requires a City of Chicago business license.You must register with the Illinois Department of Revenue (IDOR) if you conduct business in Illinois or with Illinois customers. You (or the purchaser or transferee) must complete Form CBS-1, Notice of Sale, Purchase, or Transfer of Business Assets. File an annual report for a Corporation, Not-for-Profit, or Limited Liability Company online. Incorporate a business or terminate an LLC. This system allows you to form or register a Not-for-Profit, Domestic Corporation, or Limited Liability Company or terminate an LLC online. Special use approval means that a business must complete and submit a separate application to the Zoning Board of Appeals. What is Small Claims Court? O Small Claims Court is a place where you can sue a person or business, if the amount you are seeking is.