How Do I File Taxes for a Deceased Person in Illinois?
Find out which tax returns you need to file after someone dies. See state-specific forms, deadlines, and whether tax clearance is required.
Frequently Asked Questions
At minimum, a final federal income tax return (Form 1040) and a final Illinois income tax return (IL-1040) must be filed for income earned through the date of death.35 ILCS 5/502; 35 ILCS 405/1 et seq.Verified Jul 13, 2026 If the estate earns income during administration, a federal fiduciary return (Form 1041) and Illinois fiduciary return (IL-1041) may also be required. Estates exceeding $$4,000,000 must also file a Illinois estate tax return.
The final federal and Illinois income tax returns are due april 15 following year of death (automatic 6-month extension to october 15).35 ILCS 5/502; 35 ILCS 405/1 et seq.Verified Jul 13, 2026 The fiduciary return is due april 15 (calendar year); automatic 6-month extension.
No. Certificate of Discharge from estate tax lien available via Form 700 checkbox (handled by Attorney General). IDOR Form ITR-1 available for business tax clearance but not required for probate.35 ILCS 5/502; 35 ILCS 405/1 et seq.Verified Jul 13, 2026 All tax obligations must be satisfied before making final distributions.
Yes. Illinois imposes a state estate tax on estates exceeding $$4,000,000.35 ILCS 405/2Verified Jul 13, 2026 This is separate from the federal estate tax. Estates above the state threshold must file a state estate tax return even if no federal estate tax is owed. See the full breakdown with the Illinois death tax calculator.
Yes. Estate size does not affect the requirement to file a final income tax return. A final Form 1040 is required regardless of estate value if the deceased had income. What smaller estates typically avoid is the federal estate tax return (Form 706) and the Illinois estate tax return (for estates over $$4,000,000).
The executor named in the will (or the court-appointed administrator) is responsible for filing the final income tax return and any estate tax returns. If the deceased was married, the surviving spouse can file a joint federal return for the year of death. For trust assets, the successor trustee handles fiduciary tax returns. The Illinois estate settlement plan covers all filing responsibilities in order.
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Named as Executor
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Death of a Parent
A step-by-step guide to what happens after a parent dies: the documents to find, the certificates to order, and whether probate is even required.
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Loss of a Spouse
What a surviving spouse needs to do: death certificates, survivor benefits, whether probate is even required, and the tax election that expires.
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Named as Trustee
Being named trustee means managing trust assets and carrying out the grantor's wishes. Your duties, timeline, compensation, and how to get started.
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Calculators and checklists for executors and trustees.
Petition for Probate and Letters
Prepare the application to open probate and request Letters Testamentary or of Administration.
Notice to Creditors
Prepare the creditor notice for an estate — the official state form or a notice typeset to statute, plus mailed notices for known creditors.
Small Estate Affidavit
Prepare the affidavit that collects a small estate's property without probate — the official state form or an affidavit drafted to statute, plus a presentation letter for each holder.
Estate Inventory
Prepare the probate inventory of estate property — every asset at its date-of-death value, composed to your state's statute, with the state's filing or delivery instructions.
Estate Closing
Prepare the paperwork that closes the estate — the state's closing statement, petition for discharge, or final account, with the state's closing instructions and the optional federal forms.
Letter of Instruction
Prepare the letter of instruction a bank or insurer requests during estate settlement.
How Much Does Probate Cost?
Estimate attorney fees, executor fees, court costs, and timeline for probating an estate in your state. See if the estate qualifies for simplified probate procedures.
How Much Can an Executor Charge?
Calculate how much an executor (personal representative) can charge for administering an estate. See if your state has statutory fees or uses reasonable compensation.
Who Inherits Without a Will?
Find out who inherits your estate and how much they get if you die without a will. Based on your state's intestate succession laws.
What's Fair Trustee Compensation?
Find out what's fair compensation for serving as trustee. Compare family, professional, and corporate trustee rates based on your situation.
How Much Are Estate & Inheritance Taxes?
Calculate federal estate tax, state estate tax (12 states + DC), and inheritance tax (5 states) for an estate or trust.
How Many Death Certificates Do I Need?
Calculate how many certified death certificates you need based on the assets and accounts you need to close. See state-specific ordering information.
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Illinois Estate Planning Resources
In-depth guides covering Illinois probate laws, trust requirements, and estate planning strategies.