Understanding Fair Market Value in Illinois Estates

When someone passes away in Illinois and their estate enters probate, one of the first things the court needs is an accurate inventory of what the person owned and what those things are worth. But "worth" is a loaded word. Are we talking about what the deceased paid for an item? What it would sell for at a garage sale? What an insurance company says it's worth? In Illinois probate, the answer is fair market value and getting it wrong can cause real problems with the court, the IRS, and the beneficiaries who are waiting for their share.

This guide breaks down what fair market value actually means in the context of an Illinois estate inventory appraisal, how it's determined, and what executors and administrators need to watch out for when filing with the probate court.

What Does Fair Market Value Mean in an Illinois Estate Inventory?

Fair market value (FMV) is the price that a willing buyer would pay a willing seller, both having reasonable knowledge of the relevant facts, and neither being under any compulsion to buy or sell. This definition comes from federal tax guidance and is the standard Illinois probate courts expect when executors file an estate inventory and appraisal.

It is not:

Original purchase price what the deceased paid for the asset years ago is irrelevant to its current value.
Replacement cost the cost to buy a similar new item doesn't apply here.
Insurance value insurance appraisals often reflect sentimental or replacement value, which can be significantly higher or lower than FMV.
Assessed value for property taxes county assessments in Illinois often lag well behind true market conditions.

Fair market value is specific to a point in time. For Illinois estate inventories, that point in time is the date of death. This is sometimes called the "valuation date," and every asset listed on the inventory must reflect its value as of that specific date.

When and Why Does Fair Market Value Come Up in Illinois Probate?

If you're serving as an executor or administrator of an estate in Illinois, you are legally required to file an inventory with the probate court that lists every asset the deceased owned and its fair market value. Under the Illinois Probate Act, this filing is one of your core executor responsibilities for estate asset appraisal.

The inventory matters for several practical reasons:

Court oversight The probate judge reviews the inventory to make sure the estate is being administered properly. Inflated or deflated values raise red flags.
Beneficiary expectations Heirs and beneficiaries use the inventory to understand what the estate is worth and what they might receive. Inaccurate numbers lead to disputes.
Tax reporting FMV determines potential estate tax liability at both the federal and state level. Illinois has its own estate tax with an exemption threshold that's lower than the federal one (currently $4 million for Illinois versus roughly $13 million federally as of 2024). Getting the valuation wrong can trigger unnecessary tax bills or audits.
Asset distribution When an estate is divided among multiple beneficiaries, fair market value is the baseline for making sure each person receives their proportional share.

How Is Fair Market Value Determined for Different Types of Assets?

Not all estate assets are valued the same way. The method depends on what you're appraising:

Real Estate

For homes, land, and commercial property, fair market value typically comes from a professional appraisal by a licensed Illinois appraiser. The appraiser will look at comparable sales (recent sales of similar properties in the same area), property condition, location, and current market trends. County assessor values and Zillow estimates are not accepted by probate courts as reliable FMV figures.

Financial Accounts and Securities

Bank accounts, CDs, and savings bonds are straightforward their value is the balance as of the date of death. Stocks, mutual funds, and bonds are valued at their closing price on the date of death (or the average of the high and low prices that day). Brokerage statements from the date of death serve as documentation.

Personal Property and Household Items

Furniture, clothing, electronics, artwork, jewelry, and collectibles all need a fair market value. This is where many executors struggle. A couch purchased for $2,000 three years ago might have an FMV of $200 at a date-of-death appraisal. Jewelry or fine art, on the other hand, may require a specialist appraiser. The IRS and Illinois courts expect these values to reflect what the items would actually sell for not sentimental worth.

Vehicles

Cars, trucks, boats, and recreational vehicles can be valued using resources like Kelley Blue Book or NADA Guides, adjusted for mileage, condition, and local market data. A private-party sale value is typically the closest proxy to fair market value.

Business Interests

If the deceased owned a business or a share in one, valuation gets more complex. Professional business appraisers consider factors like revenue, assets, liabilities, market position, and goodwill. This type of appraisal often requires a credentialed valuation analyst.

What Are Common Mistakes Executors Make With Estate Asset Valuation?

Errors in fair market value assignments are more common than you'd think, and they can delay probate, trigger court objections, or create tax problems. Here are the ones that come up most often:

Using online estimates for real estate Automated valuation tools are rough estimates at best. Probate courts want a professional appraisal for real property, especially for high-value homes or unique properties.
Listing items at purchase price or insurance value This almost always overstates the estate's value, which can inflate tax liability.
Undervaluing assets to reduce taxes Some executors deliberately lowball values. This is risky. If the IRS or Illinois Department of Revenue audits the estate, penalties and interest can follow. Courts may also hold the executor personally liable.
Forgetting about certain assets Digital assets (cryptocurrency, online accounts with value), life estate interests, pending lawsuits, and owed debts to the deceased all need to be included. Our guide on what assets must be listed on an Illinois estate inventory covers this in more detail.
Getting informal opinions instead of formal appraisals A friend who "knows about antiques" or a real estate agent's opinion is not the same as a written appraisal from a licensed professional. Courts and taxing authorities expect documentation.
Using a valuation date other than the date of death Every asset must be valued as of the same date: the decedent's date of death. Using a different date, even by accident, creates inconsistencies the court will question.

Do You Need a Professional Appraiser, or Can You Value Assets Yourself?

Illinois law doesn't require every single item to be appraised by a professional, but the court does require that values be reasonable and supportable. Here's a practical way to think about it:

Get a professional appraisal for real estate, high-value personal property (jewelry, art, antiques, collectibles), business interests, and any asset where the value is unclear or disputed.
Use reliable reference data for vehicles (Kelley Blue Book, NADA), publicly traded securities (closing prices), and bank accounts (account statements).
Use reasonable judgment for low-value household items, but document your reasoning. If a table is in fair condition and comparable tables sell for $50–$75 at estate sales, listing it at $60 is defensible. Listing it at $0 or $500 is not.

When in doubt, hire a professional. The cost of an appraisal is an estate expense paid from estate funds it's not something you have to cover personally. And a good appraisal protects you as the executor from later claims that you mishandled the estate.

For a full walkthrough of how the inventory form works, see our instructions on completing an estate inventory form for Illinois probate court.

What Happens if the Court or Beneficiaries Disagree With Your Valuations?

Any interested party a beneficiary, creditor, or even the court itself can object to the values listed on an estate inventory. If this happens:

The objecting party typically files a written objection with the court.
The court may order an independent appraisal or hearing to determine fair market value.
The executor may need to present their documentation: appraisals, account statements, comparable sales data, and any other evidence supporting the listed values.
The judge makes the final determination.

This process can be expensive and time-consuming, which is why getting the values right from the start matters so much. It's far cheaper to pay for a proper appraisal upfront than to defend your numbers in a contested hearing.

How Does Fair Market Value Affect Illinois Estate Taxes?

Illinois is one of the states with its own estate tax, and the threshold is significantly lower than the federal exemption. As of 2024, estates valued over $4 million may owe Illinois estate tax. The total value of the estate is determined by adding up the fair market value of all assets as of the date of death.

Because of this lower threshold, accurate FMV matters even for estates that wouldn't owe federal estate tax. An executor who accidentally overvalues assets could force the estate to pay Illinois tax it doesn't actually owe. Understating values can lead to penalties if audited.

For a deeper look at executor obligations around appraisals and filing, read our overview of understanding fair market value in Illinois estate inventory appraisal.

Quick Checklist for Getting Fair Market Value Right

Confirm the date of death This is your valuation date for every asset.
Separate assets by type Real estate, financial accounts, personal property, vehicles, and business interests each need different valuation approaches.
Hire licensed appraisers for real property, valuable personal property, and business interests. Keep the written appraisal reports in your records.
Pull account statements and market data for financial assets as of the date of death.
Use published guides (Kelley Blue Book, NADA) for vehicles with documented condition and mileage.
Be realistic about household goods Use estate sale or resale values, not replacement cost or sentimental value.
Document everything Keep appraisals, receipts, screenshots of market prices, and any other evidence that supports your numbers.
Don't guess on high-value items If you're unsure, get a professional opinion. The appraisal fee protects you and the estate.
Review the full inventory before filing Make sure nothing is missing and every value ties to the same valuation date.
File on time Illinois requires the inventory to be filed within 60 days of your appointment as executor (unless the court grants an extension). Late filings can result in the court removing you as executor.

Next step: If you're preparing to file an estate inventory, start by gathering all financial statements, property records, and titles as of the date of death. Then identify which assets need a professional appraisal and schedule those first licensed appraisers often have a two-to-four-week turnaround, and you don't want that to be the reason your inventory is late.