Illinois Estate Tax Calculator
What would Illinois and the federal government each claim on a taxable estate? Every piece below can be linked to, so it opens in a window on your reader's screen, current as of the record. No form to fill in.
2026 law · Reviewed September 3, 2026 · The full page, with methodology and sources · the terms · All tools
Embed the calculator in your page
The same engine and the same reviewed record as the tool page, in a frame: taxable estate in, Illinois and federal tax out, with the out-of-state share, the married-couple view, and the proposed-law setting. In a frame it carries no cookies, no tracking, and a visible link back to the methodology. Your site has to allow frames; most do. The link that opens it in a small window is on the professionals page.
Show the code
- In plain words.
- An estate is everything a person owns when they die: the house, the accounts, the life insurance. Illinois taxes estates above four million dollars, and the federal government taxes them above a much higher line. This tool takes the size of an estate and tells you how much each government would take, for one person or for a married couple.
- Why it matters.
- If your estate is anywhere near the Illinois line, the difference between planning and not planning can be a six-figure check. Knowing which side of the line you are on is the first step, and the number to bring to an estate attorney.
- An example.
- A single person with a six-million-dollar estate would owe Illinois about $456,000 and the federal government nothing, because six million is under the federal line. The Illinois tax is the whole bill.
- Where it stops.
- It does not value your estate for you, and it does not apply deductions, charitable gifts, or credits. If you own property in another state, or a trust already holds some of your assets, the real answer needs an attorney's return.
The facts
Seven quotable sentences, each computed by the engine from the state's published method and the 2026 figures. Quote them with the year attached.
The button shows exactly what your reader sees when they click the link. Paste the link where a link goes; it opens this list in a small window, always current as of the record, with the attribution and a link to the full page. Nothing to copy out, nothing to update later.
Show the code
- Illinois taxes estates above $4,000,000. The federal estate tax begins at $15,000,000 for deaths in 2026. Between those two lines, Illinois is the only estate tax that applies.
- A $5,000,000 all-Illinois estate owes the state $285,714 and the federal government $0. That is the state's own published example.
- Just over the line, each added dollar costs about 28.6 cents of Illinois tax. The ramp eases at about $5.4 million, where the state's credit schedule takes over.
- Illinois lets a surviving spouse inherit none of a late spouse's unused exclusion. A married couple with $7,000,000 owes Illinois $565,603 at the second death if everything passed outright to the survivor, and $0 if the first death set $4,000,000 aside.
- For an Illinois decedent with one federal exclusion, the federal tax stays at $0 until the estate reaches about $16.9 million, because the Illinois tax is deducted before the federal tax is figured.
- Property sited outside Illinois shrinks the bill in proportion. A $5,000,000 estate with half its property in Florida owes $142,857, half the all-Illinois figure, even though Florida has no estate tax.
- SB 3847 would raise the line to $8,000,000 for deaths from January 1, 2027. As of September 3, 2026: Referred to Senate Assignments on February 6, 2026; a co-sponsor was added June 26, 2026. It has not passed either chamber and is not law.
The ramp chart
Illinois estate tax against taxable estate under 2026 law. The year and the attribution are drawn into the file, so it stays honest wherever it travels.
The button shows exactly what your reader sees when they click the link. Paste the link where a link goes; it opens this chart in a small window, always current as of the record, with the attribution and a link to the full page. Nothing to copy out, nothing to update later.
Show the code
Tax by estate size
The same ten rows the chart draws, with the federal tax for one exclusion alongside. Computed from the engine; copy it as an HTML table or as plain text for a spreadsheet.
The button shows exactly what your reader sees when they click the link. Paste the link where a link goes; it opens this table in a small window, always current as of the record, with the attribution and a link to the full page. Nothing to copy out, nothing to update later.
Show the code
| Taxable estate | Illinois tax | Illinois, as % of estate | Federal tax, one exclusion | Combined |
|---|---|---|---|---|
| $4,000,000 | $0 | 0.0% | $0 | $0 |
| $4,500,000 | $142,857 | 3.2% | $0 | $142,857 |
| $5,000,000 | $285,714 | 5.7% | $0 | $285,714 |
| $6,000,000 | $456,071 | 7.6% | $0 | $456,071 |
| $7,000,000 | $565,603 | 8.1% | $0 | $565,603 |
| $8,000,000 | $680,634 | 8.5% | $0 | $680,634 |
| $10,000,000 | $926,923 | 9.3% | $0 | $926,923 |
| $12,000,000 | $1,195,517 | 10.0% | $0 | $1,195,517 |
| $15,000,000 | $1,609,310 | 10.7% | $0 | $1,609,310 |
| $20,000,000 | $2,298,965 | 11.5% | $1,080,414 | $3,379,379 |
Cite and link.
The clean address, a citation generated from the record so it can never carry a stale review date, and an address for every section so you can point a reader at the exact table or method.
Show the code
- Link
- https://consideratecapital.com/tools/illinois-estate-tax-calculator
- Citation
- Considerate Capital, "Illinois Estate Tax Calculator," reviewed September 3, 2026, https://consideratecapital.com/tools/illinois-estate-tax-calculator.
Link to a section
- The calculator https://consideratecapital.com/tools/illinois-estate-tax-calculator#calculator
- The facts https://consideratecapital.com/tools/illinois-estate-tax-calculator#facts
- Key numbers https://consideratecapital.com/tools/illinois-estate-tax-calculator#key-numbers
- How Illinois counts https://consideratecapital.com/tools/illinois-estate-tax-calculator#how-it-works
- Worked examples, official and derived https://consideratecapital.com/tools/illinois-estate-tax-calculator#examples
- The ramp chart and the size table https://consideratecapital.com/tools/illinois-estate-tax-calculator#chart
- Methodology https://consideratecapital.com/tools/illinois-estate-tax-calculator#methodology
- Sources https://consideratecapital.com/tools/illinois-estate-tax-calculator#sources
- Revision history https://consideratecapital.com/tools/illinois-estate-tax-calculator#revision-history
Everything here reads from one reviewed record, so a copied piece carries its year and its review date. When the law moves, the embed updates by itself; a copied table or chart keeps the year in its caption. Corrections are welcome through the contact page.