If you obtained a filing extension for your personal 2019 income tax return (Form 1040 or 1040-SR) and have not yet filed, today is the deadline for getting it in (unless extended because of a federally-declared disaster); you can still e-file the return. If you fail to file by today, you will owe a late filing penalty; no additional extensions can be granted. Calendar-year C corporations on extension must file Form 1120 for 2019 by today (unless extended because of a federally-declared disaster). Find a list of disaster-related extensions from the IRS (click on “2020”).