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Illinois Extends Corporate Income Tax Filing Due Date

Tax Development Oct 13, 2022

Illinois Extends Corporate Income Tax Filing Due Date

The Illinois Department of Revenue announced that the automatic extended due date of corporate income tax returns, Form IL-1120, will be extended one month, from October 17, 2022 to November 15, 2022 for calendar year 2021. The state historically has allowed an automatic extension of six months for tax returns due on the 15th day of the fourth month and an automatic extension of seven months for all other returns. This allowed corporate income tax filers an extra month beyond the federal automatic extension. The changes made to federal automatic extension dates in 2016 resulted in the loss of the extra month for corporate filers. The change announced in Information Bulletin FY2023-02 will restore the additional month extension for the current filing year. As a reminder, the extension to file the return is not an extension to pay taxes due. All taxes due must be paid by the original due date to avoid penalties and interest.

An amendment to Illinois Administrative Code Section 100.5020(b) has been proposed that would make the seven-month automatic extended due date permanent for corporate filers, by specifically designating the due date as one month after the federal extended due date.

We will keep you updated on the status of the proposal.


Mark L. Nachbar

Mary Bernard

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