How to file a sales tax return in Illinois Illinois: Sales Tax Handbook


How to file your sales taxes in Illinois

Once your business has an Illinois sales tax license and begins to make sales, you are required to start collecting sales taxes on behalf of the Illinois government and filing regular sales tax returns. This page will help you understand the basics of your tax collection and filing responsibilities.

How To Collect Sales Tax In Illinois

It is quite simple to collect taxes in Illinois if you have a physical location within state lines. The state follows a simple origin-based sales tax system; this means tax rates are established by geographical location, and the set rate is collected at the time of sale.

If you are an online retailer with tax nexus obligations in Illinois, you have a few more details to sort through. Illinois charges you with the responsibility of charging the origin-based tax rate of your customers' geographic locations. So, you must know the specific rate for the zip code to which you are shipping, and you are required to charge that particular tax rate.

Sales Tax Collection Discounts In Illinois

Illinois allows merchants to keep a small percentage of the sales tax they collect as a collection discount, which serves as compensation for the work required to comply with the Illinois sales tax regulations

The collection discount is 1.75% of tax due, although there is a minimum of five dollars each calendar year.

Your Illinois Sales Tax Filing Requirements

You have two choices for filing taxes in Illinois. You can file online at, or by mail using form ST-1. Form ST-1 can downloaded and printed at

If you have $0 in sales, but you maintain a business license, you are still required to file a zero sales tax return, despite the fact that you have no sales.

In order to determine your tax obligation, total sales and total tax collected must first be determined. A series of calculations can then be applied to these numbers based on the type of tax obligation they require. Formulas and instructions are found on the Form ST-1 Instructions page located at .

Taxes for prior months receipts are due on the 20th of each month, and late fees will accrue as follows:

* 2% up to 30 days late
* 10% after 30 days
* 90% after 90 days
* 20% after 180 days.

A 1.75% discount is rewarded to those retailers who pay their sales tax on time.

Your Illinois Sales Tax Filing Frequency & Due Dates

Your business's sales tax return must be filed by the 20th of the month following reporting period. For a list of this year's actual due dates, see our calendar of Illinois sales tax filing due dates.


Where To File Your Illinois Sales Tax Return:

Filing Your Illinois Sales Tax Returns Online

Illinois supports electronic filing of sales tax returns, which is often much faster than filing via mail.

Illinois allows businesses to make sales tax payments electronically via the internet.

Electronic payments are required for taxpayers whose local, state, and use tax liability from the prior calendar year was greater than two hundred thousand dollars. In addition, taxpayers who file their returns electronically are required to make their payments electronically as well.

You can process your required sales tax filings and payments online using the official MyTax Illinois website, which can be found here . You should have received credentials to access your MyTax Illinois account when you applied for your Illinois sales tax license.

Filing Your Illinois Sales Tax Returns Offline

While it is highly recommended that you file online using the MyTax Illinois website, it is possible to file your required sales tax reportings offline using Illinois Form ST-1, which you can download and print here . Once you have completed your required reportings, you can mail it to the state at this address:

Illinois Sales Tax Filing Address:
Illinois Department of Revenue
Retailers' Occupation Tax
Springfield, IL 62796-0001

Please note that if you file your Illinois sales taxes by mail, it may take significantly longer to process your returns and payments.

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** This Document Provided By SalesTaxHandbook **