Effective January 1, 2018, if your annual gross receipts average $20,000 or more, as determined by the Department, you are required to electronically file Form ST-1 and any other Sales and Use Tax-related return that you file (i.e., Forms ST-4, ST-8, and ST-14). See Informational Bulletin FY 2018-05-A for more information about the electronic return filing mandate.
If you already are filing your Sales and Use Tax returns using an electronic method, you do not need to do anything more than what you currently are doing. If you have not been filing your Sales and Use Tax returns using an electronic method and have been notified by the Department that you must begin to do so, please be aware that you can electronically file Form ST-1 and other related Sales and Use Tax returns for free using MyTax Illinois. You can also file Form ST-1 electronically using a direct file service through an outside vendor. See the Electronic Services for Businesses page for more information about electronic return filing and electronic tax payment options.