Authored By James L. Hamilton
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IDOR Announces Changes to the 2016 Illinois Business Income Tax Filing Due Dates

Content provided by: Illinois CPA Society

The Illinois Department of Revenue (IDOR) recently announced changes to state tax return due dates for C corporations for the 2016 filing season. See IDOR Guidance

  • Calendar Year C corporations will receive an extra month to file their returns and pay any taxes owed. The original filing and payment due date will change from March 15, 2017 to Tuesday, April 18, 2017.
  • Fiscal year C corporations, whose tax year ends on a date other than June 30, will also receive an extra month to file returns and make tax payments. Their original filing and payment due date will be changed to the 15th day of the 4th month following the close of the tax year.
  • There are no changes to original filing dates for S corporations, partnerships, trust/estates, or exempt organizations in Illinois.

BackgroundFederal Return Due Date Changes

The IDOR administrative adjustment to the C corp filing dates is in response to federal filing due date changes that were passed by Congress in 2015. These new changes will apply to 2016 tax returns prepared during the 2017 filing season.

Previously, calendar-year C and S corps were required to file by March 15, while individuals, trusts, and partnerships had to be filed by April 15. With the rise of more limited liability companies (LLC) and limited liability partnerships (LLP), there are now many more tax filings of partnership and S corp returns. There is also a large increase in the number of investors, both individuals and businesses, in pass-through entities that need information from the corporations, companies and partnerships mentioned above – before determining their own taxable income.

The new federal due dates make the partnership and S corp returns due first (3/15) and then individual and C corp returns due a month later (4/18). The extended due dates are modified in a similar manner so that the same logical flow is maintained. To maintain this logical order, states are beginning to align their filing deadlines to the new federal dates.

If you have any questions, please contact us at 847.441.8800.

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