Illinois Estate Tax 2026: $4M Exclusion and Rates

The Illinois estate tax starts above $4 million, the exclusion has not budged in years, and unlike many states it offers no way for a surviving spouse to carry over an unused exclusion.1 That makes planning matter for couples near the line. This guide tells you whether your estate owes and which form the executor files.

If you own a home and have retirement savings in Illinois, the threshold is closer than you might think.

Illinois Estate Tax at a Glance

Here is the full picture in one table. Illinois runs a graduated estate tax, administered by the Illinois Attorney General and paid by the estate before assets pass to heirs, and there is no separate inheritance tax on the people who receive the money.1

How the Illinois Estate Tax Works

The estate tax is a tax on the value of everything a person owned at death, paid by the estate itself, not by the heirs. In Illinois the tax is administered by the Illinois Attorney General, and the estate's representative files the return and pays out of estate assets before the remainder is distributed.

The exclusion is $4,000,000.1 An estate below that owes no Illinois estate tax. Above it, the estate files Form 700, the Illinois estate tax return.1

The rate is graduated, climbing in brackets to a top rate of 16 percent as the taxable estate grows.1 The $4 million figure is a filing threshold, not a credit: once an estate exceeds it, the tax is figured on the estate's value under that graduated schedule.1

How much you actually owe depends on the size of the estate, so estimate it before you assume the worst. Use the Form 700 instructions the Illinois Attorney General publishes, or have an Illinois estate attorney run the number for your estate. Two structural features make the Illinois tax tougher than the headline exclusion suggests, and they get their own section below.

What counts toward the estate is broader than people expect. The estate generally includes the home and any other real estate, bank and brokerage accounts, retirement accounts like IRAs and 401(k)s, the death benefit of life insurance the deceased owned, business interests, vehicles, and personal property. It is the gross value of what the person owned or controlled at death, not just the cash on hand. A Chicago-area homeowner with a paid-off house and a healthy retirement account can reach $4 million without ever feeling rich, which is exactly how the tax catches families who assumed it was only for the wealthy.1

No Portability, and a Frozen Exclusion

Two things about the Illinois estate tax catch families off guard.

First, the exclusion is not indexed for inflation.1 It has stayed at $4 million while home values and retirement balances climbed, so more estates cross the line every year without any change in the law. An Illinois estate that was comfortably under the threshold a decade ago may be over it today purely on appreciation.

Second, Illinois does not allow portability.1 A surviving spouse cannot use a deceased spouse's unused exclusion. In a state that does allow it, a married couple can effectively shelter close to double the exclusion. In Illinois, without planning, the first spouse's unused exclusion is simply lost. It is the kind of gap that surfaces in probate, when it is too late to fix. For couples whose combined assets are near or above $4 million, that is the single biggest reason to set up trust planning while both spouses are living. This is general information, not legal or tax advice, and an Illinois estate attorney can build the structure that fits your situation.

Consider a married couple with $7 million in combined assets. If the first spouse leaves everything to the survivor, the survivor's estate is later taxed with only one $4 million exclusion instead of the two the couple could have used.1 A credit-shelter or bypass trust fixes this: it captures the first spouse's exclusion at the first death instead of letting it vanish. The trust does the work that portability handles automatically in other states.

The general statewide exclusion remains $4 million.1 Proposals discussed in 2025 were limited to farm property and did not change it. Always confirm the current figure with the Illinois Attorney General before relying on it.

Estate Tax Is Not Inheritance Tax

These two terms get used as if they mean the same thing. They do not, and the difference decides who pays.

An estate tax is paid by the estate, out of the deceased person's assets, before anything is distributed. An inheritance tax is paid by the heirs, on what each receives, after distribution. A handful of states have an inheritance tax. Illinois does not.1 So if you inherit from an Illinois estate, you do not owe an Illinois inheritance tax on your share. Any tax owed was the estate's responsibility and was settled before you received anything.

For heirs, that means the estate tax can reduce what is left to divide, but it does not drop a separate bill on each beneficiary.

Not the Federal Tax, Not Medicaid Recovery

Two other things get confused with the Illinois estate tax. Both are different, and the distinction matters.

The federal estate tax is separate, and its exemption is far higher. For deaths in 2026 the federal exclusion is $15 million per person, more than three times Illinois' $4 million exclusion.2,1 Many estates owe Illinois tax while owing nothing to the IRS, because they fall in the gap between the two figures. The two taxes are calculated independently, on separate returns. Clearing the federal bar tells you nothing about whether you owe Illinois.

Medicaid estate recovery is not a tax at all. It is the process by which a state seeks repayment from the estate of someone who received certain Medicaid-funded long-term care. It applies to a different group of people, for a different reason, under separate rules. If a parent received Medicaid-paid nursing home care, the relevant concern is recovery, not the estate tax. We cover it fully in Medicaid estate recovery; the similar name does not make them one issue.

Learn More

Next Steps

Add up the home, the accounts, and the life insurance, and see whether the total clears $4 million.1 If you are married and near the line, the lack of portability makes early trust planning worth it.

For the exact tax and the forms, the Illinois Attorney General's estate-tax page has Form 700 and its instructions. To set up trust planning, an Illinois estate attorney can do it and confirm the current exclusion; the Illinois State Bar Association runs a lawyer referral service if you need one.

Find personalized help planning for senior care costs at brevy.com.

The information on Brevy.com is for educational purposes only and is not a substitute for professional legal, financial, or medical advice. Rules vary by state and program and change frequently. Always verify with the relevant agency or a qualified professional. Brevy is not a law firm, financial advisor, or healthcare provider.