For fiscal year, file by the 15th day of the fourth month following the tax year close (Form 1041).
If the tax year for an estate ends on June 30, 2020,you must file by October 15, 2020. If the due date falls on a Saturday, Sunday, or legal holiday, you can file on the next business day.
If more time is needed to file the estate or trust return, use IRS Form 7004, Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns, to apply for an automatic 5 1/2-month extension.
To start a Form 7004:
See the Instructions for Form 7004 on page 4 for information on where to file your Form 7004.
Definition of Fiscal year: 12 consecutive months ending on the last day of any month except December. A 52-53-week tax year is a fiscal tax year that varies from 52 to 53 weeks but does not have to end on the last day of a month.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.