Corporate Extensions Due Date
Calendar-year S corporations that filed for extensions for their federal and New York corporate tax returns that were originally due in March of 2017 must still file those returns by this Friday, September 15, 2017.
However, calendar-year C corporations that filed for extensions for their federal and New York returns that were originally due in April of 2017 get an extra month to file their federal returns, which are due on October 16, 2017.