If your business is structured as a Partnership (Form 1065), you will have a new tax filing deadline for the 2016 tax year. Your Form 1065 tax return will now be due by March 15th just like a small corporation (Form 1120S).
The deadline for regular C corporations (Form 1120) will be pushed ahead one month to April 17th and become due the same time as personal returns. For corporations with a fiscal year of July 1st to June 30th, the deadline will still be September 15th (3 months after end of fiscal year). Regular corporation extensions are now allowed a 6-month automatic extension.
Foreign bank account reports or FBARs (FinCen Form 114) will now be due on April 15th. You will also be able to file extensions for the first time on FBARs. Unlike tax returns, FBARs do not have a next-business-day rule if the deadline falls on legal Holidays or weekends.
The changes outlined above apply to the 2016 tax year which is filed during the 2017 calendar year.