You may be able to e-file your state at File Form IL-1040-X, Amended Individual Income Tax Return. Otherwise, you need to mail all forms that have changed from the original filing along with any additional forms received, w2, etc. If you are filing a federal amended return, please be aware of the rules in Amending My Return - Filing Requirements - Illinois.gov which state:
Note: If the federal change results in a refund, do not file Form IL-1040-X until you receive notification that your change has been accepted by the IRS.
Turbotax may allow e-filing of IL-1040-X, IL does not. there are required documents that must be included and they can not be included if you were to efile
What must I attach to my Form IL-1040-X?
If you are filing Form IL-1040-X because:
A) you filed a federal Form 1040X to report a federal change other
than an NOL carryback, you must include a copy of that form and
proof of federal finalization.
If your federal change resulted in an overpayment, proof of federal
finalization includes a copy of the notification you received from
the IRS stating that they accepted the changes shown on your
federal Form 1040X; e.g., a refund check, “Statement of Account,”
agreement, or judgment.
If your federal change resulted in a balance due, proof of federal
finalization includes a copy of your federal Form 1040X and a
copy of the check you sent to the IRS to pay the tax due.
If you do not have a copy of this notification, please contact the
IRS to request a tax account transcript.
B) of a change made by the IRS, you must include copies of all the
federal examining officer’s reports, including preliminary, revised,
corrected, and superseding reports.
C) of any other changes, see the instructions for Form IL-1040 and
any schedules to see what to attach.
If the change you are making requires a supporting
schedule or form, you must attach it to your Form IL-1040-X.
Without proper attachments, IL may partially or totally deny your claim.
Mail your return to:
ILLINOIS DEPARTMENT OF REVENUE
PO BOX 19047
SPRINGFIELD IL 62794-9047
actually, an e-file IL-1040-X should be rejected
I am resident of illinois and primary home in illinois, I forgot to answer those questions. I need to file IL-1040-X to claim the property tax credit back . what form / doc do I need to mail in ?
Thank you for answering the questions.
You will complete and mail in the IL-1040-X and attach Schedule ICR as well. According to the IL-1040 instructions for line 16 and the schedule ICR instructions there are no other attachments required for the property tax credit.
Complete the IL amendment by following the prompts in TurboTax. When complete, download/print the return for mailing. Include any forms that changed from the original return and add the Schedule ICR.