If you live and work in Illinois, it’s smart to know exactly how your take-home pay (net pay) is figured — so you’re not surprised on payday. This guide walks you through how to calculate a paycheck after taxes in Illinois, with real-world examples, easy tables, and planning tips to help you keep more of your earnings.
Understanding the Basics
Gross Pay vs. Net Pay
- Gross pay is the total amount you earn before any taxes or deductions.
- Net pay (or “take-home pay”) is what lands in your bank account after all withholdings, taxes, and deductions.
You want to move from gross → taxable income → withholdings → net pay.
The Main Tax Components on an Illinois Paycheck
When you calculate your paycheck in Illinois, you’ll deal with several key elements:
- Federal income tax: based on your filing status, income level, and the rates set by the Internal Revenue Service (IRS).
- FICA taxes: Social Security tax (6.2 %) + Medicare tax (1.45 %) on most wages.
- Illinois state income tax: Illinois uses a flat rate of 4.95 % in 2025 for most taxable income.
- Pre-tax and post-tax deductions: such as 401(k) contributions, HSA, health insurance premiums, union dues — these reduce your taxable income or directly reduce your take-home pay.
These components combine to determine how much you’ll actually walk away with each paycheck.
Step-by-Step Manual Calculation for Illinois
Here’s how you calculate your paycheck after taxes in Illinois, step by step. Don’t guess — know what you’ll be paid using our accurate and updated calculator.
Step 1 – Identify Your Gross Income for the Pay Period
Decide your annual salary (if salaried) or your hourly wage and pay frequency (if hourly).
Table: Example conversions
| Annual Salary | Bi-weekly (26 pays) | Monthly (12 pays) | Weekly (52 pays) |
|---|---|---|---|
| $60,000 | $2,307.69 | $5,000 | $1,153.85 |
| This helps you know the “gross pay” number for each paycheck. |
Step 2 – Subtract Pre-Tax Deductions
These are deductions taken before taxes apply, reducing your taxable income:
- 401(k) or other retirement plan contributions
- HSA (Health Savings Account) or FSA (Flexible Spending Account)
- Some health insurance premiums (if pretax)
Example: if you contribute $200 each pay period to a 401(k), subtract that from your gross pay BEFORE calculating taxable income.
Step 3 – Calculate Federal Income Tax Withholding
Federal tax depends on your W-4 form (filing status, additional withholdings, allowances) and your taxable income. For simplicity: estimate based on brackets, or use a withholding table.
Note: Your actual paycheck withholding may differ from your final tax liability at year-end.
Step 4 – Calculate FICA Taxes
- Social Security tax: 6.2 % of your wages (up to the annual wage base).
- Medicare tax: 1.45 % of all wages; if you earn over $200,000 (single filer) you pay an extra 0.9 % Medicare tax.
These apply to most wage earners.
Step 5 – Calculate Illinois State Tax
Since Illinois uses a flat rate, you multiply your taxable income (after pre-tax deductions) by 4.95 %.
Example: if your taxable income that pay period is $2,100, then Illinois tax = $2,100 × 4.95 % = $103.95.
Step 6 – Subtract Post-Tax Deductions and Other Withholdings
Some deductions apply after taxes are calculated:
- Union dues, wage garnishments, voluntary charitable giving taken out of pay.
- Some post-tax insurance contributions.
Subtract these from what remains. Workers in Austin can verify deductions using the Texas paycheck calculator.
Step 7 – Compute Your Take-Home Pay (Net Pay)
Formula:
Net Pay = Gross Pay – (Federal Income Tax + FICA + State Tax + Pre-Tax Deductions + Post-Tax Deductions)
Let’s walk through a concrete example:
Example 1: Salary scenario
- Annual salary: $60,000
- Pay frequency: Bi-weekly (26 pays) → Gross = $2,307.69
- Pre-tax deductions: $200
- Post-tax deductions: $50
Calculation:
- Taxable income = $2,307.69 − $200 = $2,107.69
- Illinois tax ≈ $2,107.69 × 4.95% ≈ $104.33
- FICA: Social Security = $2,107.69 × 6.2% ≈ $130.85; Medicare = $2,107.69 × 1.45% ≈ $30.56 → Total FICA ≈ $161.41
- Federal tax: assume $220 (varies widely)
- Net Pay ≈ $2,307.69 − ($220 + $161.41 + $104.33 + $50) ≈ $1,771.95
Example 2: Hourly + overtime scenario
- Hourly wage: $22 → 40 hours regular + 5 hours overtime at 1.5× (so overtime rate $33)
- Gross for week: (40 × $22) + (5 × $33) = $880 + $165 = $1,045
- Pre-tax deduction: $0; Post-tax deduction: $0
- Taxable income = $1,045
- Illinois tax ≈ $1,045 × 4.95% ≈ $51.75
- FICA: Social Security = $1,045 × 6.2% ≈ $64.79; Medicare = $1,045 × 1.45% ≈ $15.15 → Total ≈ $79.94
- Federal tax: assume $95
- Net Pay ≈ $1,045 − ($95 + $79.94 + $51.75) ≈ $818.31
Pay Frequency and Scenario Comparisons
Weekly vs Bi-Weekly vs Monthly – Does It Matter?
Yes — the frequency of pay affects how much you receive each period and how you budget, though annual totals tend to be similar.
Table: Salary $60,000 annual
| Pay Frequency | Gross per period | Estimated Net (after typical deductions) |
|---|---|---|
| Weekly (52) | $1,153.85 | ~$790-$820 |
| Bi-weekly (26) | $2,307.69 | ~$1,750-$1,800 |
| Monthly (12) | $5,000 | ~$3,700-$3,800 |
Bonus / Commission / Multiple Jobs
- Bonuses and commissions may be withheld at supplemental wage rates, which could be higher than your regular withholding.
- If you have multiple jobs, combined earnings might push you into a higher federal effective tax rate and affect FICA limits. It’s wise to monitor total income and adjust your W-4 accordingly.
- Be aware: in Illinois your state tax rate remains the same (4.95 %) regardless of income level, unlike states with progressive rates.
Illinois-Specific Considerations & Planning Tips
Flat State Tax Rate – What That Means
Illinois charges the same income tax rate (4.95 % in 2025) for almost all taxable income — there are no brackets based on income level.
Implications:
- Simpler tax calculation for state tax.
- Your state tax doesn’t increase if you earn a lot more (unlike some states).
- Because of the flat rate, how you manage deductions matters more for take-home.
Pre-Tax Accounts to Boost Take-Home Pay
Using pre-tax options reduces your taxable income and helps increase your net pay.
- 401(k) or employer retirement plan: contributes pre-tax income.
- HSA/FSA: health savings accounts reduce taxable income.
- Pre-tax health insurance premiums: reduce gross taxable pay.
Quick Table:
| Salary Level | Pre-Tax Contribution | Annual Tax Saved (approx) |
|————-|———————-|—————————-|
| $60,000 | $2,000 | $2,000 × (Fed avg ~12% + IL 4.95%) ≈ $340-$350 saved |
Watch Out for Withholding Mistakes
- If you don’t update your W-4 after major life changes (marriage, new job, second job), your paycheck might be out of sync with your tax liability.
- If you’re a contractor or freelancer working in Illinois, taxes work differently — you won’t have the usual payroll withholdings, so you’ll need to estimate and send quarterly payments.
- Note: Illinois does not impose a local-income-tax in most jurisdictions, so you don’t typically have extra municipal tax on payroll withheld for many workers.
Comparing Illinois to Other States
If you’re considering relocation or comparing job offers, take note:
- Illinois’s flat tax simplifies things vs states with brackets.
- But your overall tax burden (income + property + sales tax) might differ significantly.
- For example: If you earn $60,000, your state tax in Illinois is roughly $2,970 before deductions (4.95 % of $60,000). In a progressive state your state tax might be higher or lower depending on brackets.
Use this to negotiate offers and budget accordingly. Texans can explore local differences via the Houston paycheck calculator.
Downloadable Tool & Interactive Worksheet
Want to plug in your own numbers and see the result? Create or download a simple Google Sheets or Excel template:
- Input fields: annual salary/hourly wage, hours worked, pay frequency, pre-tax deductions, post-tax deductions.
- Automatically calculate: gross per period, federal withholding estimate, FICA, Illinois state tax, net pay.
You can use this tool to simulate scenarios: what if you increase 401(k) by $50 / pay, or switch to bi-weekly from monthly, or take overtime. The Los Angeles paycheck calculator shows how California’s city taxes vary.
Frequently Asked Questions
Q1: How do I calculate my take-home pay in Illinois after taxes?
You start with gross pay for your pay period, subtract pre-tax deductions, apply federal tax withholding, FICA, Illinois state tax (~4.95 %), subtract post-tax deductions — the remainder is your net pay.
Q2: What is the Illinois state income tax rate and how does it affect my paycheck?
Illinois uses a flat rate of 4.95 % for the 2025 tax year. That means you’ll pay 4.95 % of your taxable income (after pre-tax deductions) in state income tax.
Q3: How are federal taxes, Social Security and Medicare deducted from an Illinois paycheck?
Federal income tax is based on your W-4 settings and taxable income. Social Security tax is 6.2 % of wages (up to the annual limit). Medicare tax is 1.45 % of wages — plus an extra 0.9 % if you earn over $200,000 (single filer). These apply before considering Illinois state tax.
Q4: How does pay frequency (weekly vs bi-weekly) impact net pay in Illinois?
While your annual net pay will be similar, pay frequency affects how much you receive each check and can impact budgeting. Bi-weekly pays simply mean fewer checks with higher amounts; weekly means more frequent, smaller checks. Withholding is generally based on regular period.
Q5: Can pre-tax deductions like 401(k) or HSA reduce my Illinois paycheck taxes?
Yes. Pre-tax contributions reduce your taxable income for both federal and Illinois state tax. That means less tax withheld and higher net pay each period.
Q6: How does having multiple jobs affect my paycheck after taxes in Illinois?
With multiple jobs, your combined income might increase your federal tax rate or push you through FICA wage caps faster. Illinois state tax remains 4.95 % but you’ll want to monitor combined taxable income and update your W-4 to avoid under-withholding.
Q7: Are there local or municipal income taxes in Illinois in addition to the state tax?
In most cases, no — Illinois does not have a statewide municipal income tax added on top of the 4.95 % state rate. However, always check if your city/county has specific local rules.
Q8: How are bonuses and commissions taxed in Illinois on your paycheck?
Bonuses/commissions are taxable wages and subject to FICA, federal withholding (often at a higher supplemental rate), and Illinois state income tax at 4.95 %. Because withholding may be higher, ask your employer how they process supplemental wages.
Q9: If I move to a state with no income tax, how will my Illinois take-home pay compare?
If your income stays the same but you relocate to a no-income-tax state, you’ll eliminate state tax payments (like Illinois’s 4.95 %). That boosts your net pay — but remember other cost factors (cost of living, property tax, sales tax) may change.
Q10: What are common mistakes that reduce take-home pay in Illinois?
- Not updating W-4 after major life changes.
- Missing out on pre-tax contributions (401(k), HSA) that could reduce tax.
- Failing to account for overtime, bonuses or second jobs when estimating taxes.
- Relying solely on payroll withholding without eventual reconciliation- at-year-end you might owe tax.
Bettye is the creator of CityPaycheckCalculator.com, a resource designed to help individuals quickly and accurately estimate their take-home pay across U.S. cities. With a strong focus on clarity, accuracy, and user experience, Bettye provides reliable paycheck calculators and helpful insights to support smarter financial decisions. Her mission is to make complex payroll and tax information simple and accessible for everyone.