When is the deadline for electronic filing of Form 990 with a fiscal year ending July 31, 2021 and an
IRS due date of December 15, 2021?
The earlier of:
(a) 11:59:59 pm on 12/15/2021; and
(b) A nanosecond before your internet service or computer goes down if it can't be revived before (a).
Business efile will probably shut down shortly after Dec 15 and reopen in January sometime. IRS has not announced the dates yet.