1. What is Illinois Income Tax?

Illinois has a flat income tax rate of 4.95% for all taxpayers regardless of income level. This calculator helps estimate your state income tax liability based on your taxable income.

2. How Does the Calculator Work?

The calculator uses the Illinois flat tax formula:

Where:

• \( Income \) — Your taxable income in USD
• \( 0.0495 \) — Illinois flat tax rate (4.95%)

Explanation: The calculation is straightforward as Illinois uses a flat tax system rather than progressive tax brackets.

3. Importance of Tax Calculation

Details: Accurate tax estimation helps with financial planning, budgeting, and ensuring you set aside enough money for tax payments.

4. Using the Calculator

Tips: Enter your taxable income in USD (gross income minus any deductions or exemptions). The amount must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: Is Illinois income tax really flat?
A: Yes, Illinois has a flat 4.95% income tax rate for all taxpayers since 2017, regardless of income level.

Q2: Are there any deductions or exemptions?
A: While the rate is flat, you may qualify for certain deductions or exemptions that reduce your taxable income.

Q3: Does this include local taxes?
A: No, this calculator only estimates state income tax. Some Illinois municipalities have additional local taxes.

Q4: When are Illinois taxes due?
A: Illinois state income taxes are typically due April 15th, matching the federal deadline.

Q5: Is retirement income taxed in Illinois?
A: Most retirement income (pensions, 401(k), IRA) is not taxed in Illinois, which could affect your taxable income.