For paper returns, the filer should write the word deceased, the deceased person's name and the date of death across the top. File the final income tax returns of a deceased person for current and prior years, pay any balance due and claim the refund.File an estate income tax return. The form requires the claimant to provide information about the deceased taxpayer, including their name, Social Security number, and date of death. The Illinois Department of Revenue (IDOR) sends letters and notices to request additional information and support for information you report on your tax return. For paper returns, the filer should write "deceased," the person's name and the date of death across the top. Who should sign the tax return. You must submit two required documents to verify your identity - one from each category listed below, within 60 days of the date of this letter. For a copy of the deceased person's tax return, submit Form 4506, Request for Copy of Tax Return. There's a fee for each return you request.