The Corporation Income Tax Return is due 75 days after the established year end of the company. If the company closes its books on December 31st, then the return is due by March 15th. If the company’s year end is July 31st, then the return is due 75 days after that, or no later than October 15th.
What happens if you can’t file your return timely, and you file an extension? Form 7004 or the extension provides an automatic 6 month extension to file the 1120 or 1120S Form only. It does not provide an extension for any money which may be owed. If you are asking these questions in the first place, then it’s time for a new accountant.