How do I correct an error on my electronically filed Form IL-1040 return?
If you filed your IL-1040 electronically, you may also file Form IL-1040-X through MyTax Illinois only for tax year 2021. For all other years, file by paper using Form IL-1040-X, Amended Individual Income Tax Return.
If you are filing Form IL-1040-X due to a federal change, do not file until you receive notification from the IRS showing it was accepted. For more information, refer to the Form IL-1040-X Instructions.