On March 31, 2020, the USPTO announced extensions to the time allowed to file certain patent- and trademark-related documents and to pay certain required fees. In brief, some deadlines due between 3/27/20 and 4/30/20 (inclusive) are extendable for 30 days upon submission of a request and appropriate statement attributing the delay to the COVID-19 outbreak materially interfering with timely filing or fee payment. Details can be found in the official Patent and Trademark notices.
Of note, patent deadlines that can be extended include responses to substantive Office Actions, Notices of Appeal, and Issue fee payments. Trademark deadlines that can be extended include responses to Office Actions, statements of use, affidavits of use or excusable non-use, and renewal applications. However, extensions are not available for the 1-year due dates for filing US or PCT applications after the filing of a provisional application. Extensions are also obviously not available for filing applications to pre-date public disclosures or other bar dates.
A full list of USPTO Notices regarding COVID-19 can be found on the USPTO Coronavirus Resource page.