IL Sales Tax Filing States

How to File an Illinois Sales Tax Return

by Jennifer Dunn

How to File an Illinois Sales Tax Return

Save time filing your Illinois sales tax return with this step-by-step guide. Don’t have time for all this hassle? Let TaxJar AutoFile your Illinois sales tax return for you so you can get back to running your business!

What You’ll Need

1) Your TaxJar Illinois Sales Tax Report

2) Your Illinois sales and use tax account number

3) Your My Tax Illinois username

4) Your My Tax Illinois password

5) Your bank account number and routing number

How to File an Illinois Sales Tax Return

1) Login to TaxJar – If you don’t have a TaxJar account, don’t worry. You can sign up for TaxJar today and we’ll import your transactions from the platforms and shopping carts you sell on (including Amazon, Walmart, eBay, PayPal, Square, Shopify, and many more). No more compiling clunky sales tax reports from multiple shopping carts and trying to compile them by hand before filling out your Illinois return.

2) Open your TaxJar Illinois Sales Tax Report

See your sales tax collected in Illinois in the TaxJar sales tax app

3) Decide whether to use your Actual Sales Tax Collected Report or Expected Sales Tax Due report. (Note: In most cases, we recommend using the numbers from your “Actual Sales Tax Collected Report,” but you may want to use your “Expected Sales Tax Due Report” if you were not collecting sales tax and need to report sales tax you should have collected. Read more about Expected and Actual sales tax reports here.)

4) Login to MyTax Illinois with your Username and Password.

5) On the home screen, choose form ST-1.

Filing Illinois sales tax return form ST-1Form ST-1, Step 2: Taxable Receipts

6) Find your “Gross Sales” in Illinois – this number is at the top of your TaxJar Illinois state report.

Find your Illinois gross sales in TaxJar

7)  Enter your Gross Sales on your Illinois form ST-1 on line 1 “Total Receipts” under “Step 2: Taxable Receipts.” The Illinois filing system will automatically round this number to the closest dollar amount.

How to fill out Illinois sales tax return Line 1 Total Receipts

8) Enter your deductions on line 2  – To enter your deductions, you’ll need to click the “From Schedule A, Line 30” link beneath line 2.

How to enter deductions on your Illinois sales tax return

Schedule A

This link will take you to your Illinois Schedule A, which looks like this:

How to fill out Illinois sales tax return schedule A

9) Enter taxes collected on Line 1 of Schedule A – You can find this number on your TaxJar Illinois state teport by mousing over the (?) sign next to “Deductions/Exemptions.” For this line, use the number next to “Tax Collected.”

How to enter Deductions on Illinois sales tax return schedule A

9) If you have other items listed under Deductions/Exemptions, fill those out on Schedule A, Line 16. In this case, the customer has refunds. Be sure to label line 16 as “Refunds,” etc.

How to enter refunds on Illinois sales tax return

10) Check your work – From here, all of your deductions will total up on Line 17. This should match the total “Deductions/Exemptions” line on your TaxJar Illinois state report.

11)  Return to the ST-1 form – That will conclude Schedule A for most online sellers, but you may have special circumstances where you will have information to enter on other lines on Schedule A. To continue fling your Illinois sales tax return, click the small “Go back to ST-1 Main” link at the bottom of Schedule A.

Illinois sales tax filing complete Schedule A

Form ST-1, Step 3: Tax on Receipts

Now you will be back on form ST-1 and will tackle “Step 3: Tax on Receipts.”

How to file a sales tax return in Illinois

12) Enter your sales within Illinois on Line 4a. You can find these numbers on your TaxJar Illinois state report. The number you will want to enter will be under “Taxed Sales.”

How to enter sales within Illinois on an Illinois sales tax filing

Note: If you have multiple locations within Illinois, this will take you to form ST-2 where you can find a list of your locations. You can read more about registering multiple business locations in Illinois here.

13) Enter sales for your first location – On Form ST-2, click the location for which you wish to enter sales. (Remember, you will only need to do this if  you have multiple Illinois locations.)

How to fill out sales within Illinois on Illinois state sales tax form

14) If applicable, repeat this process for all your Illinois locations.

Pro Tip: Do you see a location on your TaxJar Illinois state report but not on your Illinois sales tax filing? You can add a new location from your MyTax Illinois Account by logging in and clicking “Maintain Locations” on the home screen. If you do this during the filing of your return, be sure to save your current return with the “Save” link in the top right-hand corner and come back to it.

How to add a new business location in MyTax Illinois

15) Enter sales from outside Illinois on line 6a.  In this case, you don’t have to enter individual locations. Just take the “Taxed Sales” number from the “Sales from locations outside Illinois” line on your TaxJar Illinois state report.

How to enter sales from locations outside Illinois in Illinois sales tax filing

16) Check your work – Now the totals from your entries on lines 4a and 6a should total the amount you entered in Step 2: Line 1. If they do not, you’ll see an error like the below. Keep in mind that because Illinois’ sales tax system rounds numbers up and down to the nearest dollar, this may be slightly off. You can make sure the numbers match up by adjusting the dollar amount on Line 6a.

How to handle an Illinois sales tax filing error

Form ST-1, Step 4

17) Take your discount – Good news! If you filed on time in Illinois, you are eligible for a Retailer’s Discount. If you qualify, check the box next to “Calculate discount, if applicable” under Line 10 in Step 4 of your Illinois ST-1. Line 10 will show you how much sales tax you get to keep. On the remainder of the form, that total will be subtracted from the amount you owe to the state of Illinois.

How to take the Illinois Retailers Discount on your Illinois sales tax return

Form ST-1, Step 7

18) Check the entire form for errors –  To do this, double check the amount on Line 25 on form ST-1 matches with your “State + Local Taxes” number at the bottom of your TaxJar Illinois state report. (If you are using your “Expected Sales Tax Due” tab to file this return, this line will be labeled “Expected State + Local Taxes.”)

Expected sales tax due in Illinois

19) Double check that you didn’t collect any excess tax – Do this by comparing the number on your Schedule A Line 1 with the amount on the amount on Form ST-1 Line 9. If the amount on Schedule A is greater than the amount on Line 9, you’ll want to include this amount on Line 22 of your Form ST-1. (Why does this happen? Incorrect sales tax settings in your shopping carts or marketplaces can lead to you collecting an excess amount of sales tax from a customer. If you make this mistake, states require that you pay this excess tax collected back to the state.)

Submitting your Illinois Return and Paying Illinois Sales Tax

20) Submit your return – When you’re sure your return is correct, scroll up and click “Submit” at the top of the page. You’ll be asked to re-enter your MyTax Illinois password, then you’ll receive a confirmation number showing your return was successfully submitted.

Submit your Illinois sales and use tax return

21) Pay the sales tax you owe – Click “Proceed to Payment” on the confirmation screen. This will walk you through entering your bank account information and paying your sales tax balance. You’ll be asked to enter your password again to confirm that you want to pay, and you’ll be giving a payment confirmation number separate from your filing confirmation number.

22) You’ll also want to log into TaxJar and record the payment in your Payment History.

And you’re done with your Illinois sales tax return. Would you rather not have to deal with this again? You can sign up for TaxJar AutoFile and we’ll file your Illinois sales tax return for you!

Have questions or comments about filing an Illinois sales tax return? Start the conversation in the comments, or ask other sellers and sales tax experts over at

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