Illinois sales tax: the formula and a worked example
The simple formula for sales tax in Illinois, how to include local rates, and how to reverse it from a receipt.
Key facts
| Place | Illinois |
|---|---|
| Sales tax | State sales tax |
| Standard rate on file | 6.25% |
| Multiply net price by | 1.0625 |
| Tax share of a gross price | 5.88% |
| Currency | USD |
The formula
Multiply the pre-tax price by the combined rate as a decimal. At the 6.25% state rate, that is the price times 0.0625. Add the result to the price for the total.
Worked example
Here is the calculation with sample figures. Change any number in the Illinois Sales Tax Calculator to run your own.
| Price | $250.00 |
| Tax rate (%) | 6.25% |
| Tax | $15.62 |
|---|---|
| Price incl. tax | $265.62 |
Finding the price before tax
To go backwards from a total, divide by 1.0625. Subtracting 6.25% from the total gives the wrong answer because the tax was calculated on the pre-tax amount.
Quick reference at 6.25%
Common amounts in Illinois, worked both ways: adding tax to a net price, and extracting it from a price that already includes tax.
| Amount | Tax on net amount | Gross (net + tax) | Net if amount includes tax |
|---|---|---|---|
| $10.00 | $0.62 | $10.62 | $9.41 |
| $50.00 | $3.12 | $53.12 | $47.06 |
| $100.00 | $6.25 | $106.25 | $94.12 |
| $250.00 | $15.62 | $265.62 | $235.29 |
| $500.00 | $31.25 | $531.25 | $470.59 |
| $1,000.00 | $62.50 | $1,062.50 | $941.18 |
| $5,000.00 | $312.50 | $5,312.50 | $4,705.88 |
How Illinois compares
Standard rates on file for other states. A difference of a few points matters most on high-value purchases and on cross-border sales.
| Place | Rate on file | Compared with 6.25% |
|---|---|---|
| Georgia | 4% | lower |
| Hawaii | 4% | lower |
| Idaho | 6% | lower |
| Indiana | 7% | higher |
| Iowa | 6% | lower |
| Kansas | 6.5% | higher |
Using the calculator step by step
- Open the Illinois Sales Tax Calculator.
- Type your figures into the numbered lines. Results update as you type.
- Check the rate field. It starts at 6.25%; change it if a reduced rate, local surcharge or exemption applies to you.
- Read the result on the receipt panel, and use the formula shown under it if you need to explain the figure to a client or colleague.
Key terms
- Gross amount
- The amount after tax is added, which is usually what a consumer pays.
- Marginal rate
- The rate applied to the next unit of income. It decides how much of a raise or a deduction you keep.
- Taxable income
- Income left after allowances and deductions, on which the tax rates are applied.
- Zero rate
- A rate of 0% on a taxable supply. Unlike an exemption, the seller can usually still reclaim tax on costs.
- Tax credit
- An amount subtracted directly from the tax bill, worth its full face value.
Common mistakes to avoid
- Subtracting the percentage from a total instead of dividing.
- Forgetting local rates.
Run your own numbers. The Illinois Sales Tax Calculator updates as you type and shows the formula it uses.
Frequently asked questions
How do I calculate Illinois sales tax?
Price times the combined rate. At the state rate alone, price times 0.0625.
How do I remove sales tax from a Illinois receipt?
Divide the total by 1 plus the combined rate.
This article is general information for planning, not tax advice. Rates and rules change; confirm with your tax authority or a qualified adviser.