Illinois Capital Gains Tax Calculator 2025

Use this free calculator to estimate capital gains tax in Illinois, including federal rates, NIIT when applicable, and Illinois's state treatment (flat 4.95% state rate).

State treatment: Flat 4.95% state rate·Official source ↗

Capital Gains Calculator

Federal · NIIT · All 50 states

2026 ratesIRS verified

Follow the three steps, save the sale, then calculate. Required fields are marked with *.

Your tax profile

These apply to every sale in this estimate.

Tax year

Filing status

State

Annual taxable income (before these gains)

Capital loss carried from prior years

What you sold

Prices and quantity for this lot. Give it a name if you will add more than one sale.

Asset type

Asset name

Buy price

Sell price

Quantity / units

Selling expenses

Repurchased within 30 days (wash-sale check)

When you bought and sold

The IRS uses these dates to decide short-term vs long-term rates.

Buy date

Sell date

Next: Save this sale to the order log, then click Calculate now. Tax results do not update until you calculate.

Order log

Sales included in this tax estimate.

Please fill in the details to see your results. Follow the three steps on the left, then save a sale here.

Illinois capital gains tax overview

Illinois capital gains tax planning starts with the federal rules, then layers on Illinois's own treatment (flat 4.95% state rate). This calculator estimates both so you can see a combined effective rate before you sell stocks, crypto, real estate, or other capital assets.

Federally, short-term gains (held one year or less) are taxed as ordinary income, while long-term gains generally use 0%, 15%, or 20% preferential rates for tax years 2025 and 2026. High earners may also owe the 3.8% Net Investment Income Tax when MAGI exceeds the IRS threshold for their filing status.

Illinois applies a flat state rate to capital gains in our model (Flat 4.95% state rate). Flat-rate states are simpler to estimate than graduated systems, but deductions, credits, and local rules can still change your final bill — always confirm with the official revenue agency.

Illinois figures in this model are drawn from the official source we cite for the state: https://tax.illinois.gov/. Confirm the current-year statute or agency page before you file — rates and special rules can change.

Use the calculator above with filing status and income to stack federal long-term or short-term tax, NIIT, and Illinois state tax. Compare nearby states from the links below, review our methodology for data sources (including Illinois's official reference), and consult a CPA before filing. This page is educational and not tax advice.

Illinois rate snapshot

Category	flat
Summary	Flat 4.95% state rate
Abbreviation	IL
Flat / modeled rate	4.95%

Always verify rates with theIllinois revenue agencyand review ourmethodology. Not tax advice.

FAQ

Illinois FAQs

How does Illinois tax capital gains?

Illinois is modeled as a flat-rate state: Flat 4.95% state rate. We apply that modeled rate to taxable gains after federal asset-class rules. Federal short-term and long-term capital gains tax, and the 3.8% Net Investment Income Tax when MAGI exceeds the IRS threshold, can still apply.

Is the Illinois rate the same for short-term and long-term gains?

In this calculator, Illinois's modeled flat rate applies to taxable gains regardless of holding period. Federal treatment still differs for short-term vs long-term. Always confirm Illinois statutes for any special exclusions.

Where do these Illinois rates come from?

Our Illinois model cites https://tax.illinois.gov/. Deductions, credits, and local taxes are not fully modeled — treat the state line as a planning estimate.

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