Will County sales tax on general merchandise starts at 7.00% in unincorporated areas and runs to 8.75% or higher inside cities and villages that add their own local tax. The spread comes from stacking: the State of Illinois sets the floor, the Regional Transportation Authority adds a fixed slice because Will County sits in its service area, and each municipality decides what, if anything, to layer on top. Where you tap your card inside the county changes the total, sometimes by more than a point.
How the Rate Is Built
Three pieces make up what you pay at the register. Illinois imposes a 6.25% retailers’ occupation tax on most tangible goods. The RTA adds 0.75% everywhere in Will County because the county is one of six in its jurisdiction.1Illinois Department of Revenue. Mass Transit District Sales Tax Will County itself does not currently add a countywide sales tax. Together, those produce the 7.00% floor.
Municipalities stack their own rates on top. Joliet, for example, adds 1.75% in home rule tax, bringing the total to 8.75%. Other towns in the county fall anywhere from a quarter point to more than a point and a half above the floor. The same television can cost a few dollars more at one store than at another a couple of miles away, purely because of which city line it sits inside.
Business District Surcharges
Some municipalities designate a commercial corridor as a business district and add up to another 1% retailers’ occupation tax, in quarter-percent increments.2Illinois General Assembly. 65 ILCS 5/11-74.3-6 If a receipt shows a rate higher than the city’s general rate, the store is probably inside one of those zones. The districts are tied to specific redevelopment or infrastructure projects and are time-limited, so they do not apply citywide, let alone countywide.
Why Rates Vary From Town to Town
Home rule status is the main reason. Under the Illinois Constitution, any municipality over 25,000 residents is automatically a home rule unit, and smaller towns can opt in by referendum. Home rule cities can impose additional sales taxes in quarter-percent increments with no legal ceiling.3Illinois Department of Revenue. Home Rule Sales Taxes That gives larger Will County cities like Joliet, Bolingbrook, and Romeoville room to set rates that match their budgets.
Non-home-rule municipalities are capped. They can add up to 1% in quarter-percent increments, and certain tax types require voter approval.4Illinois Department of Revenue. Home Rule and Non-home Rule Sales Taxes That cap is why smaller villages in the county tend to carry lower combined rates than the bigger cities.
What You Pay on Different Purchases
Illinois splits tangible goods into categories, each with its own rate treatment: general merchandise at the full combined rate, drugs and medical appliances at a reduced state rate plus local taxes, and titled property like vehicles with their own reporting process.5Illinois Department of Revenue. Sales and Use Taxes
Groceries
Effective January 1, 2026, Illinois eliminated the 1% state tax on grocery food.6Illinois Department of Revenue. FY 2026-11, Municipal and County Grocery Occupation Tax Rate Changes “Groceries” here means food for off-premises human consumption and excludes alcohol, soft drinks, candy, and prepared meals. The same law lets municipalities and counties adopt their own 1% local grocery tax by ordinance, so whether your grocery bill still carries a local 1% depends on whether your city or Will County itself passed one. The RTA’s share on groceries continues either way.
Medicine and Medical Appliances
Prescription and nonprescription medicines, along with medical appliances, are taxed at a reduced 1% state rate.7Illinois Department of Revenue. Taxpayer Answer Center A product qualifies when its labeling claims it treats, cures, or mitigates disease, illness, injury, or pain.8Illinois Department of Revenue. Tax Rate Information for Retail Sales of Food and Medicine (PIO-115) Local taxes still apply, so the final price at a Will County pharmacy sits above that 1% in most locations.
Vehicles and Other Titled Property
Cars, trucks, motorcycles, boats, and trailers are taxed at the same 6.25% state rate as general merchandise, but you don’t pay it at the register.9Illinois Department of Revenue. Use Tax on Titled or Registered Tangible Personal Property Vehicle buyers remit through the Secretary of State’s office or the Department of Revenue. For private-party sales, the buyer is responsible for paying the tax directly.
Services
Pure services, such as haircuts, legal advice, or accounting, are generally not subject to Illinois sales tax. Tax enters the picture only when the service provider hands you tangible property as part of the job. A mechanic’s diagnostic labor isn’t taxed; the replacement part is.
Online and Out-of-State Purchases
Starting January 1, 2026, an out-of-state retailer or a marketplace facilitator like Amazon, eBay, or Etsy must collect and remit Illinois sales tax once it generates $100,000 or more in cumulative gross receipts from Illinois buyers in the prior 12-month period.10Illinois Department of Revenue. FY 2026-12, Destination-Based Retailers’ Occupation Tax Changes The old alternative threshold of 200 separate transactions was eliminated at the start of 2026.
When a remote seller or marketplace meets that threshold, it charges tax at the rate in effect at your delivery address. An order shipped to Joliet carries Joliet’s 8.75% rate; the same order shipped to an unincorporated address in Will County carries 7.00%. Marketplace facilitators handle collection for their third-party sellers, so individual sellers on those platforms generally don’t register separately.10Illinois Department of Revenue. FY 2026-12, Destination-Based Retailers’ Occupation Tax Changes
If you buy from an out-of-state seller that doesn’t collect Illinois tax, you owe use tax yourself: 6.25% on general merchandise and 1% on qualifying drugs and medical appliances.11Illinois Department of Revenue. Use Tax Rates You get credit for sales tax another state already charged, but if that state’s rate was lower, Illinois wants the difference. If your total annual use tax liability is $600 or less, you can report it on Form ST-44 by April 15 of the following year or on your IL-1040. Above $600, you file ST-44 and pay by the last day of the month after each purchase.12Illinois Department of Revenue. Form ST-44 Instructions In practice, most online retailers now collect at checkout, so use tax mostly comes up for private purchases from individuals or small out-of-state sellers.
If You’re Collecting Sales Tax as a Seller
Retailers selling tangible goods in Will County collect and remit through Form ST-1, filed on the MyTax Illinois portal at mytax.illinois.gov.13Illinois Department of Revenue. What is MyTax Illinois and How Do I Access It? IDOR assigns monthly, quarterly, or annual filing based on your average monthly tax liability, with returns due by the 20th of the month following each reporting period for monthly filers.14Illinois Department of Revenue. ST-1 Instructions for Reporting Periods January 2026 and After
File and pay on time and you keep a small collection allowance: 1.75% of the tax due or $5 per calendar year, whichever is greater, capped at $1,000 per month.15Illinois Department of Revenue. ST-1 Instructions Miss the deadline and the discount disappears. Late-payment penalties jump from 2% in the first 30 days to 10% after that, so if a payment will be late, get as much in as you can before the 31-day mark.16Illinois Department of Revenue. Penalties and Interest for Illinois Taxes Interest accrues at 7% annually through at least June 30, 2026, and IDOR resets the rate every six months.17Illinois Department of Revenue. Interest Rates