Form IL-8453 is for electronic filing so you will not need to complete it if you are mailing your Illinois return in.
If you are sending your return without a payment, mail your return to:
ILLINOIS DEPARTMENT OF REVENUE
SPRINGFIELD IL 62719-0001
If you are sending a payment with your return, mail your return to:
ILLINOIS DEPARTMENT OF REVENUE
SPRINGFIELD IL 62726-0001
Remember to attach a copy of the W2s and 1099s.
Helpful Info:
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