How far back can I file an amended return to claim an overpayment based on changes to my federal return?
Answer #729 -- ( Published 05/30/2008 08:46 AM | Updated 08/08/2012 10:01 AM )
How far back can I file an amended return to claim an overpayment based on changes to my federal return?
If your federal change decreases your Illinois tax and you want a refund, you must file an amended return (claim for refund) within two years plus 120 days of federal finalization.
