Plus Deutsch is German for German, henceforth the explaination on why the Pennsylvania Dutch are called that when they are really German and not Dutch. The Dutch from the Netherlands also got their ethnic name derived from the German term Deutsch as well believe it or not. If you're Dutch, then you are from Denmark.
1 Deadline for filing a 2015 personal, partnership, or calendar year estates/trusts tax returns or extension.  The return or extension must be postmarked or transmitted for e-filing by Monday, April 18, 2016 (April 19 for Maine and Massachusetts residents).
Tax Deadlines in Calendar Year 2017 for 2016 Returns. Extended deadline is October 2, 2017. The deadline for C-corp returns is the 15th day of the fourth month following the end of the corporation's fiscal year if the corporation is on a fiscal rather than a calendar year.