The Illinois Department of Revenue urges residents who missed the April 15th income tax deadline to file their returns as soon as possible. Submitting late returns promptly can significantly reduce the amount of penalties and interest owed. For those who received a six-month extension, the deadline to file is October 15. Officials stress that timely action benefits both individuals and the state. Detailed instructions, forms, and additional resources can be found at the department’s official website: tax.illinois.gov. Residents are encouraged to review their filing status and avoid unnecessary costs by taking prompt action.
“While the filing deadline has passed, the longer you wait, the more it could potentially cost you due to penalties and interest,” explained IDOR Director David Harris. “Whether you owe money or are due a refund, it is important to get your return filed and take that first step.”
An extension of time to file does not extend the amount of time to pay any taxes owed. If taxpayers determine that taxes will be owed, they must use Form IL-505-I, Automatic Extension Payment for Individuals, to pay and avoid penalties and interest on taxes not paid by April 15, 2025.
