Illinois Estate Tax Calculator

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Illinois Estate Tax Calculator

Instant estimate using the State Death Tax Credit table and Illinois apportionment (for nonresidents). This widget is an educational estimate. For exact results, use the official Illinois A.G. calculator, which applies the full interrelated computation on Form 700 Lines 3 & 5.

Worldwide gross estate — USD Debts & expenses — USD Spousal bequests (marital deduction) — USD Charitable bequests — USD Adjusted taxable gifts (federal) — USD Included in Illinois computation. Illinois-situs assets — USD Nonresidents: IL real + tangible. Residents may leave blank.

Advanced (optional): QTIP & direct 700 overrides

Illinois QTIP elected in this estate — USD Subtracts from Line 3 per Form 700. Prior Illinois QTIP added back — USD Adds to Line 3 at survivor’s death. Override Form 700 Line 3 (IL Tentative Taxable Estate) — USD Override Form 700 Line 5 (Line 3 + Adjusted Gifts) — USD Decedent was a nonresident?

Results (educational estimate)

Estimated Line 3 — IL Tentative Taxable Estate

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Estimated Line 5 — Line 3 + Adjusted Gifts

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ATE used (Line 5 − $60,000)

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Tentative IL tax (before apportionment)

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Apportionment factor

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Estimated IL estate tax (after apportionment)

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Open the official Illinois A.G. Estate Tax Calculator →

How to Use the Illinois Estate Tax Calculator

This tool estimates Illinois estate tax under 35 ILCS 405. It mirrors the Form 700 framework and the state death tax credit table. Results are for planning only—final liability depends on your filed return, appraisals, and Illinois AG/Treasurer guidance.

Select residency
- Illinois residents: Use full worldwide estate; apportionment defaults to 1.000.
- Nonresidents: Enter Illinois-situs assets (IL real estate & tangibles); the calculator applies an IL fraction.
Enter gross estate & deductions (debts/expenses, marital, charitable), plus adjusted taxable gifts.
Advanced: Apply IL-only QTIP and/or override Line 3 and Line 5 to match your workpapers.
Review results: Line 3, Line 5, ATE, tentative IL tax, fraction, and estimated IL tax due.

Tips: Use current appraisals for IL real/tangible property; keep deduction support. For nonresidents, document situs and avoid creating an IL business situs for intangibles.

Next: Forms & Deadlines · Nonresident Guide · Planning