Filing a decedent's final return is usually the responsibility of the executor or administrator of the estate. But if neither is named, a survivor must do it. The return is filed on the same form that would've been used if the taxpayer were still alive, using information from the decedent's financial records as well as the settlement of the estate. Enter "Deceased," the deceased taxpayer's name and the date of death across the top of the return. Failure to enter this information may cause a delay in processing the return. The filing deadline is April 15 of the year following the year of the taxpayer's death.

A surviving spouse can file a joint return with his or her deceased spouse as long as the surviving spouse did not remarry before the end of the year. If the surviving spouse remarried before the end of the year, the filing status for the deceased spouse is Married Filing Separately.