Illinois probate is governed by the 755 ILCS 5/ — Probate Act of 1975, filed in the Circuit Court in the county of the deceased's domicile. Illinois is not a Uniform Probate Code state, but its independent administration procedure (755 ILCS 5/28) substantially reduces court involvement — the Executor acts independently without mid-administration court approval, and the estate can close without a formal hearing in many cases. Illinois's 6-month creditor period runs from the date of death (not first publication) — longer than most states. The $4 million estate tax threshold means many Illinois estates are subject to state estate tax.
Pursue independent administration when available. If the will authorizes independent administration or all heirs consent in writing, request it at the opening hearing. It eliminates most mid-administration court filings and allows a simpler closing — cutting months off the supervised probate timeline and significantly reducing costs.
When Independent Administration Is Available
Illinois's independent administration (755 ILCS 5/28-1) is available when:
- The will expressly authorizes independent administration, OR
- All interested persons (heirs, legatees) consent in writing
Under independent administration, the Executor can collect assets, pay debts, manage property, and make distributions without prior court approval for most actions. The estate closes by sending a closing notice to all heirs — a formal hearing is not required in most cases.
Supervised administration is required or appropriate when:
- The will does not authorize independent administration and a party will not consent
- An heir contests the will or disputes the distribution
- A creditor disputes a claim or the estate is insolvent
- A minor or incapacitated beneficiary's interests require court protection
- Court oversight is needed to resolve disputes between interested parties
6-month creditor period from the date of death — not from publication. Under 755 ILCS 5/18-12, creditors have 6 months from the DATE OF DEATH to file claims. The creditor clock started on the day the person died. Publishing notice promptly is still required to formally bar claims, but publishing does not extend or shorten the 6-month period. Plan your timeline accordingly — you cannot close the estate until at least 6 months after the date of death.
Phase-by-Phase: Illinois Probate
Phase 1: Filing (Month 1)
- Complete the Petition to Admit Will to Probate and for Letters Testamentary (or Petition for Letters of Administration if no will) — forms at illinoiscourts.gov
- File the petition and the original will with the Circuit Court clerk in the county of domicile
- Pay the filing fee ($150–$300 depending on county; Cook County fees tend to be higher)
- Receive a scheduled court hearing date — typically 1–3 weeks out
- Indicate whether you will seek independent administration (755 ILCS 5/28)
- Assess whether the gross estate may exceed $4 million — if so, begin tracking for Form IL-706
Phase 2: Opening Hearing and Appointment (Month 1)
- Attend the Circuit Court hearing before the assigned judge
- Present the original will and required documents
- Receive the Order Admitting Will to Probate and Order Appointing Executor
- File the Executor's oath and acceptance of office
- Obtain certified copies of Letters Testamentary — order 10–12; each institution requires its own original
- If independent administration is authorized, receive the Order granting it at this hearing
- Post bond if required by court order (unless waived by the will)
Phase 3: Notice (Promptly after appointment)
- Publish Notice to Claimants in a newspaper of general circulation in the county for three consecutive weeks
- Publish as soon as possible after appointment — the notice formally starts the claim filing process
- Important: The 6-month creditor bar period runs from the DATE OF DEATH (755 ILCS 5/18-12) — not from first publication. The creditor clock has been running since death regardless of when you publish
- Send written notice directly to all known creditors
- Mail written notice to all heirs and legatees via certified mail with return receipt
Phase 4: Inventory (Within 60 Days of Appointment)
- Apply for the estate's EIN at irs.gov/ein; open an estate bank account using the EIN and Letters Testamentary
- Prepare the Inventory listing all probate assets with date-of-death fair market values
- Obtain real estate appraisals from a licensed Illinois appraiser
- Track total gross estate value — if approaching $4 million, confirm Illinois estate tax applies and begin Form IL-706 preparation
- File the Inventory with the Circuit Court within 60 days of appointment (755 ILCS 5/14-1)
Phase 5: Claims and Taxes (Months 1–7)
- Wait for the 6-month creditor period to expire from the DATE OF DEATH (755 ILCS 5/18-12)
- Review all creditor claims; disallow invalid claims in writing within the required period
- Pay valid claims in priority order: administration expenses → funeral costs → family allowance → federal tax debts → medical expenses of last illness → other debts
- File the deceased's final Illinois Form IL-1040 (due April 15) and federal Form 1040
- File Illinois Form IL-1041 (fiduciary income) if the estate earns income during administration
- File Illinois Form IL-706 (estate tax) if the gross estate exceeds $4 million — due within 9 months of death
Phase 6: Distribution (After All Debts and Taxes Paid)
- Distribute cash, securities, and personal property per the will or Illinois intestacy law (755 ILCS 5/2)
- Prepare and record an Executor's Deed for each real property at the county recorder of deeds
- Obtain signed receipts and releases from each legatee
- Document all distributions in the Final Account or closing notice
Phase 7: Closing (Month 7+)
- Under independent administration: Send a closing notice to all heirs and legatees with a summary of administration — a formal court hearing is not typically required. The estate closes 30 days after notice is mailed (unless an heir objects).
- Under supervised administration: Prepare a Final Account listing all income, expenses, and distributions. File the Petition for Final Account and Order of Distribution. Attend the closing hearing. Receive the Order of Distribution.
- Close the estate bank account after closing
- Retain all estate records for at least 7 years
Illinois Income Tax and Estate Tax: What the Estate Owes
Illinois flat 4.95% income tax — plus Illinois estate tax over $4 million.
- Form IL-1040 — deceased's final Illinois individual income tax return; due April 15 of the following year; covers Jan. 1 through date of death
- Form IL-1041 — Illinois Fiduciary Income and Replacement Tax Return; required if the estate earns income during administration (interest, rent, capital gains, dividends)
- Personal Property Replacement Tax: Illinois estates pay an additional 1.5% PPRT on net income, bringing the combined effective rate to 6.45%
- Form IL-706 — Illinois Estate and Generation-Skipping Transfer Tax Return; required if gross Illinois estate exceeds $4,000,000; rates 0.8%–16%; due within 9 months of death
- No Illinois inheritance tax — all beneficiaries receive their share free of state inheritance tax regardless of relationship
- Federal returns still required — federal Form 1040 (final) and federal Form 1041 (if estate income exceeds $600)
Illinois estate tax at $4 million — well below the federal threshold. The federal estate tax exemption in 2025 is approximately $13.6 million. Illinois's exemption is only $4 million — meaning many Illinois estates that owe nothing federally still owe Illinois estate tax. The marital deduction exempts assets passing to a surviving spouse from Illinois estate tax, but assets passing to children or other beneficiaries are fully subject to the tax.