Illinois Sales Tax Calculator
Published: 4 November 2026 · Updated: 4 November 2026
A $100 purchase in Chicago costs $110.50 at the till — 6.25% Illinois state sales tax plus 4.25% county, city and transit taxes, after the August 2026 transit increase. Enter your own price below.
Illinois sales tax is 6.25% at state level, with local taxes pushing Chicago to 10.50% combined since 1 August 2026. This calculator adds or reverses the tax at any Illinois rate, instantly and free.
Researched by MixKhazana Team · Last updated 4 November 2026 · Data: Illinois 2026 figures from the Illinois Department of Revenue: 6.25% state rate, Chicago 10.50% combined since 1 August 2026, statewide average combined rate 8.98% (Tax Foundation, July 2026)
What this calculator does
This calculator works out Illinois sales and use tax on any purchase. Illinois charges a 6.25% state Retailers' Occupation Tax on most retail sales of tangible goods, and counties, municipalities and special districts layer their own taxes on top — Cook County adds 1.75%, the City of Chicago 1.25% and the regional transit authority 1.25%, taking Chicago to 10.50% since the transit increase of 1 August 2026. Outside the Chicago region, combined rates are lower: the statewide average is about 8.98%, and areas with no local tax pay just the 6.25% state rate. The state's 1% grocery tax ended on 1 January 2026, so groceries now carry only local grocery taxes where a municipality has adopted one, while drugs and medical appliances remain at a 1% state rate.
How to use
- Enter your price in dollars.
- Choose Add sales tax for a shelf price or Remove sales tax for a till total.
- Pick the combined rate for your city — 10.50% in Chicago, 8.98% for the statewide average, 6.25% with no local tax.
- Click Calculate Sales Tax for the tax amount plus the net and total figures.
The formula
Adding tax: Tax = Net price × rate, and Total = Net price × (1 + rate). Removing tax: Net price = Total ÷ (1 + rate), and Tax = Total − Net price. So at Chicago's 10.50% combined rate, $100 net becomes $100 × 1.105 = $110.50, while $110.50 at the till strips back to $110.50 ÷ 1.105 = $100 net with $10.50 of tax. The state/local split inside that 10.50% is 6.25% state + 1.75% Cook County + 1.25% city + 1.25% transit — the split matters for filing, but the customer only ever sees the combined total.
Worked example
Sofia buys a $200 jacket in Chicago, where the combined rate is 10.50%:
- State tax: $200 × 6.25% = $12.50
- County, city and transit tax: $200 × 4.25% = $8.50
- Total sales tax: $21.00; till total: $221.00
- Reverse check: $221.00 ÷ 1.105 = $200.00 net, with $21.00 of tax inside it
Had Sofia bought the same jacket where only the state rate applies, she would have paid $212.50 — $8.50 less. Try the widget with $200 at 6.25% to see the difference.
Sales tax rates
| Area / case | Split | Combined |
|---|---|---|
| Chicago (Cook County) | 6.25% + 4.25% local | 10.50% |
| Statewide average combined | 6.25% + ~2.73% local | 8.98% |
| Area with 1% local tax | 6.25% + 1.00% local | 7.25% |
| No local tax (state rate only) | 6.25% + 0% | 6.25% |
Frequently asked questions
What is the Illinois sales tax rate in 2026?
Illinois charges a 6.25% state sales tax (the Retailers' Occupation Tax), and counties, cities and special districts add their own taxes on top, so combined rates run from 6.25% to over 11% depending on the address. The statewide average combined rate is about 8.98% (Tax Foundation, July 2026).
How much sales tax is on a $100 purchase in Chicago?
In Chicago the combined rate is 10.50% since 1 August 2026, so a $100 net purchase carries $10.50 of sales tax and costs $110.50 at the till. The split is 6.25% state + 1.75% Cook County + 1.25% City of Chicago + 1.25% regional transit tax.
Why did Chicago's sales tax rise to 10.50%?
Chicago's rate was 10.25% for years, then rose to 10.50% on 1 August 2026 when the regional transit tax increased by 0.25 percentage points across the six-county Chicago region (Illinois Department of Revenue bulletin FY 2026-34). At 10.50% Chicago has one of the highest combined sales tax rates of any major US city.
How do I reverse-calculate sales tax from an Illinois total?
Divide the total by 1 plus the rate: at Chicago's 10.50%, net = total ÷ 1.105 and tax = total − net. So $110.50 ÷ 1.105 = $100 net with $10.50 of tax. Select “Remove sales tax” in the calculator and enter the till total.
Is food taxed in Illinois?
The statewide 1% grocery tax ended on 1 January 2026, so groceries now carry only local grocery taxes where a municipality has adopted its own (up to 1%). Drugs and medical appliances are still taxed at a 1% state rate. Most other tangible goods are taxed at the full general merchandise rate.
What is Illinois' economic nexus threshold for remote sellers?
Since 1 January 2026 Illinois uses a sales-only economic nexus threshold of $100,000 in Illinois sales over the preceding 12 months — the old 200-transaction test was removed. Remote sellers above that threshold must collect Illinois tax.
What official source are the Illinois sales tax rates based on?
The 6.25% state rate and the Chicago 10.50% combined rate come from the Illinois Department of Revenue's tax rate database and rate files effective 1 August 2026, including bulletin FY 2026-34 on the transit tax increase. For the exact rate at a specific address, use the Department's tax rate lookup tool.