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Question

Where do I file an Illinois estate tax return?

Answer

Illinois estate tax returns are filed with the Illinois Office of the State Treasurer. The return is due within nine months of the decedent’s death. An estate planning attorney or qualified tax advisor can assist with preparation and filing.

Related FAQs

Where can I find help with Illinois estate tax planning?

Should I use an LLC to hold Illinois real estate if I’m not an Illinois resident?

Is a will or a trust better for reducing Illinois estate tax?
Tax Planning Estate Planning Asset Protection Trusts Tax Basics Tax Tips & Tricks Protecting Your Legacy Inherited Wealth Generation FAQs
Last Updated Aug. 17, 2026
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