You (or the purchaser or transferee) must complete Form CBS-1, Notice of Sale, Purchase, or Transfer of Business Assets. Chicago Business Direct is the City's new and improved platform that combines all of your city tax and license needs in one place.Learn about Chicago, IL sales tax rates, including state, county, city, and special sales taxes. Get the latest info for compliance in 2024. This comprehensive guide explores the complexities of Illinois small business tax. When selling a business in Illinois, common tax implications include capital gains tax on the sale of business assets and potential state taxes. Chicago sales tax details.