This page covers Illinois sales and use tax duties, numbers, changes and penalties. Start with the overview. Multi-state sellers can also read about sales tax nexus, our sales and use tax service and the amnesty update.
What the law requires
| Requirement | In plain words | Where to look |
|---|---|---|
| Register | Sign up with IDOR (Form REG-1, MyTax Illinois) before selling, leasing or hiring | ROT section 2a |
| Collect and file | Collect the State plus local rate; file Form ST-1 by the 20th after the period (IDOR assigns monthly, quarterly or annual filing); annual returns are due 20 January | Form ST-1 instructions |
| File electronically | Required at average annual gross receipts of $20,000 or more, unless waived | ROT section 3 |
| Document resale | A valid CRT-61 and an active buyer account ID; keep it at least 3.5 years | CRT-61 instructions |
| Pay use tax | Self-assess on taxable purchases where no Illinois tax was charged | IDOR ROT page |
| Remote sellers | Keep location data for destination sales, or accept the 15% undetermined-location rate | IDOR bulletin FY 2026-12 |
Key numbers and dates
| Item | Amount or date | Year in force | Source |
|---|---|---|---|
| State rate | 6.25% general merchandise; 1% qualifying drugs and medical appliances | 2026 | Form ST-1 instructions |
| State grocery tax | Ended; local governments may charge 1% by ordinance | From 1 Jan 2026 | IDOR bulletin FY 2026-03 |
| Transit tax (NITA), up 0.25 point | Cook County: 1.25% general merchandise, 1.50% grocery and drugs. DuPage, Kane, Lake, McHenry, Will: 1.00% on all three | From 1 Aug 2026 | IDOR bulletin FY 2026-34 |
| Remote seller threshold | $100,000 of gross receipts only | From 1 Jan 2026 | 35 ILCS 120/2 |
| Vendor's discount | 1.75% of tax or $5 a year if greater, capped at $1,000 a month | Returns due from 1 Jan 2025 | 35 ILCS 120/3 |
Source: Illinois Department of Revenue rate file
Recent and pending changes
| Date | Change | Status |
|---|---|---|
| 1 Jan 2025 | Leasing goods became retail; remote retailers moved to destination-based tax | In force |
| 1 Jan 2026 | State 1% grocery tax and the 200-transaction test ended | In force |
| 1 Aug 2026 | Transit tax rose 0.25 point in six counties | In force |
| 1 Aug to 31 Oct 2026 | Remote Retailer Amnesty: sales from 1 Jan 2021 to 30 Jun 2026 taxed at 9% (6.25% items) or 1.75% (1% items); penalties and interest waived on full payment, or a plan requested by 31 Oct 2026 and completed; some fees excluded | Ends 31 October 2026; open as of 27 Oct 2026 |
| 1 Jan 2027 | 10% Targeted Advertising Services Tax (providers over $1,000,000 of Illinois receipts) and 0.2% Digital Asset Tax (brokers collect); neither is a sales tax | Enacted, pending |
Penalties and enforcement
IDOR enforces these taxes. A dispute usually starts with an audit or a Notice of Tax Liability, and the protest deadline is 60 days from a notice stating protest rights. The Tax Tribunal hears cases over $15,000 of tax.
| Tier | Amount |
|---|---|
| Late filing | Lesser of $250 or 2% of the tax; second tier up to $5,000 |
| Late payment | 2% (1 to 30 days late), 10% (31 or more), 15% after an audit starts |
| Books and records | $1,000 first failure, $3,000 each later |
| Unpaid trust tax | Responsible person who willfully fails to file or pay: personal liability for tax, penalty and interest |
| Criminal | Selling without registering is a Class A misdemeanor; unfiled or false returns and evasion can be felonies, graded by amount |
Official sources
- Illinois Department of Revenue: Retailers' Occupation Tax
- Illinois Department of Revenue: Form ST-1 instructions
- Illinois Department of Revenue: Sales tax rate machine-readable files
- Illinois Department of Revenue: Bulletin FY 2026-12, remote retailers
- Illinois General Assembly: 35 ILCS 120/3
This page is a plain-language summary. The official source controls if there is any difference.