If your business makes taxable sales to customers in Illinois, you may need to register for an Illinois sales tax account before collecting sales tax. This 2026 guide explains who must register, what information you need, and how to complete the registration process through MyTax Illinois.
For broader information about Illinois sales tax rules, rates, and taxability, see the Illinois Sales Tax Guide. For details on filing deadlines and how to submit returns, see the Illinois Sales Tax Filing Guide.
Quick answers: Illinois sales tax registration
A quick overview of the authority, registration portal, nexus threshold, and other essentials for registering in Illinois.
| Fact | Detail |
|---|---|
| Authority | Illinois Department of Revenue |
| Registration portal | MyTax Illinois |
| Economic nexus threshold | $100,000 in annual sales or 200 separate transactions into Illinois |
| Registration fee | Free |
| Renewal period | No periodic renewal required |
Who must register for Illinois sales tax
You must register for an Illinois sales tax account if your business has a sales tax nexus in the state. This usually applies when a business:
- Exceeds the economic nexus threshold of $100,000 in annual sales or 200 or more separate transactions into Illinois in the current or previous 12-month period, or;
- Has a physical presence in Illinois, such as an office, employee, warehouse, or inventory stored in the state.
Illinois's dual threshold means you must register once you cross either the dollar amount or the transaction count, whichever comes first.
Once you exceed the threshold, you should register before making further taxable sales in Illinois. Digital goods and SaaS are taxable in Illinois, so software businesses selling to Illinois customers should pay particular attention to whether they have crossed the threshold. If you're unsure whether your business has nexus, see the Illinois Sales Tax Guide for a broader explanation.
How to register for Illinois sales tax
Sellers can register online through MyTax Illinois, the state's centralized tax portal. This is the same portal you will use to file returns and make payments after registration.
Information you need before registering
Before applying for an Illinois sales tax account, have this information ready:
- Your Social Security number (if registering as a sole proprietor with no employees)
- Your Employer Identification Number (EIN), if your business has one (required for corporations, partnerships, and most LLCs)
- North American Industry Classification System (NAICS) code for your primary business activity
- The date of your first sale in Illinois
- Your business address and any Illinois locations, if applicable
Registration steps
Follow these steps to register for an Illinois sales tax account.
1. Create your MyTax Illinois login
Set up your MyTax Illinois account credentials.
- Choose a username and password
- Set up your security information
- This login is used for all future filings, payments, and account management
If you already have a MyTax Illinois account for another tax type, you can add a sales tax account to your existing login.
2. Provide your business information
Enter your business name, address, type of entity, and any Illinois locations.
- Remote sellers without an Illinois location should indicate they are selling remotely
- Illinois uses destination-based sourcing for remote sellers. You charge tax based on where the buyer is located
- Home-rule municipalities in Illinois may impose additional local taxes on top of the state rate; your MyTax Illinois account covers state-administered taxes
3. Registration fee
Illinois does not charge a fee to register for a sales tax account. Registration through MyTax Illinois is free.
4. Submit your application
Review your entries and submit the application.
- You will receive an on-screen confirmation after submission
- A confirmation email is typically sent shortly after submission
5. Receive your Illinois Account ID
Once approved, you will receive:
- Your Illinois Account ID number (used for filing and payments)
- Your assigned filing frequency (monthly, quarterly, or annually, based on expected tax liability)
- Access to MyTax Illinois for filing, payment, and account management
What happens after registration
After registering, you must begin collecting Illinois sales tax on taxable sales and file returns based on your assigned filing frequency. Illinois uses an origin-based sourcing rule for in-state sellers but a destination-based rule for remote sellers, so out-of-state businesses should charge tax based on the buyer's location.
Keep in mind that local home-rule municipalities may impose additional taxes beyond the 6.25% state rate. Some home-rule municipalities administer their own taxes separately from the state, which may require additional registration or remittance steps. Digital goods and SaaS are taxable in Illinois, so software businesses should factor this into their compliance process.
➡ Learn more about Illinois sales tax rates, taxability, and nexus in the Illinois Sales Tax Guide
➡ See how to file and pay Illinois sales tax in the Illinois Sales Tax Filing Guide
Note: At Quaderno we love providing helpful information and best practices about taxes, but we are not certified tax advisors. For further help, or if you are ever in doubt, please consult a professional tax advisor or the local tax authorities.
Need help registering across multiple states?
Watch our webinar: US Sales Tax Registration & Filing Tips + AMA. Learn how international sellers register, file, and manage US sales tax compliance across multiple jurisdictions.
Note: At Quaderno we love providing helpful information and best practices about taxes, but we are not certified tax advisors. For further help, or if you are ever in doubt, please consult a professional tax advisor or the tax authorities.
