A 6.25% state rate plus up to 4.75 percent in local county and city add-ons.
Combined tax rate
8.98%
Sales tax
$9.03
Total with tax
$109.03
State portion
$7.25
Local portion
$1.78
Tax on $1,000
$90.30
| Scenario | Rate | Tax on $100 | Total on $100 |
|---|---|---|---|
| State rate only | {rate}% | {rate_m} | {rate_100} |
| Typical (state + average local) | {combined}% | {combined_m} | {combined_100} |
| Highest (state + max local) | {maxrate}% | {maxrate_m} | {maxrate_100} |
Illinois combines a high state rate with substantial local add-ons. Chicago sits at the top of the range, while many downstate counties are close to the state rate alone. Grocery items are taxed at a reduced 1 percent rate.
Enter the amount your customer pays, not your cost. The most common mistake is applying the rate to a pre-tax price that already includes an earlier tax adjustment, which compounds the error across every sale.
If you quote prices before tax, decide whether your displayed price includes tax. Businesses that add tax at checkout are simpler to run because the rate is collected from the buyer rather than built into your pricing. Businesses that quote tax-inclusive prices need to back the tax out of the headline figure, which is where most rounding errors appear.
For budgeting, use the typical combined rate of 8.98 percent rather than the state rate alone. Using 6.25 percent will understate your effective tax burden by about 2.73 percentage points, and that gap compounds across every sale in the year.
Sales tax applies to tangible goods and certain services, but the exemptions differ substantially between states and often between product categories within a state. The categories most commonly treated differently are:
Because these categories are treated differently at the state level, a calculator based on a single rate will always be approximate for a mixed basket. For a business buying or selling mostly one category, the statewide average is a reasonable working figure.
Selling into Illinois without registering is the mistake that carries the largest penalty. Registration obligations generally follow economic nexus, which is a sales threshold rather than a physical presence rule.
The practical sequence is: track cumulative sales into Illinois from the start, register with the Illinois revenue department once you approach $100,000, begin collecting at the applicable local rate, and file returns on the required schedule even if you have no employees or property in the state.
The penalty for periods you should have been registered but were not is typically calculated per unfiled return and can exceed the tax owed, so the cost of late registration grows quickly. Where marketplace providers such as major online marketplaces collect on your behalf, that does not satisfy your own registration obligation in most states.
The 6.25 percent figure is the statewide base rate. What a buyer actually pays is the base rate plus county, city and special district add-ons, and those vary enough within Illinois to change the final number by several percentage points. A customer in one county may pay close to 6.25 percent while another in a different county pays more than 8.98 percent.
This matters most for businesses that quote prices without tax and add it at checkout. Using the statewide average of 2.73 percent is a reasonable planning figure, but it will be wrong at both ends of the range, and for any customer in a high-rate area the error is systematically in your favour until it is not.
Illinois has a state sales tax rate of 6.25 percent. County and city add-ons average a further 2.73 percent, so the typical combined rate is about 8.98 percent. The highest combined rate in the state reaches about 11 percent in areas with the largest local additions.
Illinois is destination-based, meaning the tax rate follows where the buyer is located rather than where the seller is based. For most goods shipped to a Illinois customer, the destination rate applies. Exemptions exist, particularly for groceries in some states, so not every item is taxed at the standard rate.
Statewide averages hide a wide range. A single Illinois county can add nothing while another adds more than 4.75 percent, so two customers 30 miles apart can pay different rates. For an exact figure, look up the specific city or county at the point of sale, use the state revenue department address lookup tool, or use automated rate lookup software that resolves by customer address.
Registration depends on your sales volume and whether you have physical presence in the state. A common threshold is $100,000 in annual sales. Once you exceed it, you are generally required to collect Illinois sales tax on remote sales, register with the Illinois revenue department, and file periodic returns even without a physical location in the state.
It depends on the circumstances. Most states treat shipping separately from the taxable sale, so charges for shipping a taxable item are generally taxable when the seller arranges delivery. Exceptions exist: some states exclude separately stated freight charges, and others exempt shipping on items that are not taxable at all, such as medicines. If you charge shipping as part of a single undifferentiated price, that amount is usually treated as taxable in Illinois.
In most states, yes. When a marketplace facilitates the sale and collects Illinois sales tax on your behalf, that usually satisfies the collection obligation for that transaction, but it does not remove your own registration and filing duty once you cross the economic nexus threshold. Sellers who assume the marketplace handles everything frequently discover a registration requirement after the fact, when penalties for unfiled returns have already accumulated.
Sales tax rates differ substantially between states, and a business shipping across the country needs to charge the destination rate in each one. These related state calculators cover the rates most often compared with this one.
For a full comparison of every rate, see the US state sales tax overview.
Rates as of July 1, 2026, from Tax Foundation midyear state and local sales tax data. State and county rates change; verify with the Illinois department of revenue before relying on a specific figure for invoicing or filing.