The Illinois state ID number on a 1099-G sits in Box 10b, labeled “State identification no.” It’s the state-assigned identification number for whichever Illinois agency sent you the form: the Illinois Department of Employment Security (IDES) if you received unemployment benefits, or the Illinois Department of Revenue (IDOR) if you received a state tax refund. If your tax software keeps rejecting what you’ve entered, you’re almost certainly looking at the wrong box.
Which Box Holds the Number
The bottom of Form 1099-G has three state-related boxes, and mixing them up is the single most common reason filers get stuck:
- Box 10a shows the two-letter state abbreviation (IL for Illinois).
- Box 10b shows the state identification number. This is the one your software is asking for.
- Box 11 shows the dollar amount of state income tax withheld from your payments.
The IRS instructions for Form 1099-G describe Box 10b as “the filer’s state identification number” and define it as “the filer’s identification number assigned by the individual state.”1Internal Revenue Service. Instructions for Form 1099-G It identifies the Illinois agency that paid you. It is not your Social Security number, your IL-PIN, or your driver’s license number.
A lot of online guidance tells people to pull the number from Box 11. That is wrong. Box 11 is a dollar amount of tax withheld. If you’ve been trying to enter a figure that looks like money into an ID field, that’s your problem.
What To Do If Box 10b Is Blank
Some 1099-G forms arrive with Box 10b empty. The IRS instructions note that the state information boxes are “provided for your convenience only and need not be completed for the IRS,”1Internal Revenue Service. Instructions for Form 1099-G which means the issuing agency can legally leave them off.
First, check the payer information block at the top of the form. That’s the unnumbered area with the agency’s name, address, and ZIP code. Some agencies print a state identification number inside or next to that block instead of putting it in Box 10b.
If it still isn’t there, retrieve a fresh copy from the agency that issued the form. For unemployment benefits, that’s IDES. For a state tax refund, that’s IDOR.
Getting Your 1099-G From IDES
IDES posts 1099-G forms through its online claimant portal, and the online version is identical to the mailed one. The state ID number will be in Box 10b on the retrieved form.2Illinois Department of Employment Security. 1099-G Tax Form To pull yours:
- Log into your IDES account. You need an ILogin registration to reach any IDES account, the 1099-G portal included.
- Open the “Individual Home” dropdown and select “Request 1099-G.”
- Answer the security questions. You’ll need your Social Security number, date of birth, driver’s license or state ID, and your first and last name.
- Pick the tax year and click “View 1099-G.” Forms going back seven years are available.
IDES only mails paper 1099-G forms to claimants who did not opt into electronic delivery, which is why many people never receive one in the mail. If you’d rather not use the website, you can request a copy through the IDES automated phone system, Teleserve, at (312) 338-4337.
Getting Your 1099-G From IDOR
If your 1099-G came from IDOR because you received a state tax refund, you can look it up through MyTax Illinois without creating an account. On the MyTax Illinois homepage, find the “Inquiries for Individuals” panel and select “Look up my Form 1099-G.”3Illinois Department of Revenue. Individual Income Tax Non-login Functions That gets you the current year. For the prior three years, you’ll need to create a MyTax Illinois logon.
One thing to know before you go hunting: IDOR only issues a 1099-G to taxpayers who itemized their federal return in the prior year and had an overpayment of $10 or more.3Illinois Department of Revenue. Individual Income Tax Non-login Functions If you don’t fit that description, there may not be an IDOR 1099-G to find.
If you believe the form you do have is wrong, IDOR instructs you to write to the Taxpayer Assistance Division at PO Box 19001, Springfield, IL 62794-9001.4Illinois Department of Revenue. 1099-G
Entering the Number in Tax Software
When you reach the 1099-G section of your tax software, you’ll see a field labeled “State Payer’s ID,” “State ID Number,” or something close. Type the string from Box 10b exactly as it appears, letters and dashes included.
Leaving the field empty will often cause the Illinois return to be rejected on e-file, because IDOR can’t match the payment to the agency that issued it. Entering the withholding figure from Box 11 by mistake produces the same rejection. If you’re filing on paper, copy the Box 10b number carefully onto the line that corresponds to the state payer identification for the 1099-G income you’re reporting.