Generally, nonimmigrants must depart the United States before their authorized period of admission expires. However, we recognize that nonimmigrants may unexpectedly remain in the United States beyond their authorized period of stay should apply for an extension or change of status in advance. Should this occur, the following options are available to nonimmigrants:

Apply for an Extension. Most nonimmigrants can mitigate the immigration consequences of COVID-19 by timely filing an application for extension of stay (EOS) or change in status (COS). USCIS continues to accept and process applications and petitions, and many of our forms are available for online filing. 

If You File in a Timely Manner. Nonimmigrants generally do not accrue unlawful presence while the timely-filed, non-frivolous EOS/COS application is pending. Where applicable, employment authorization with the same employer, subject to the same terms and conditions of the prior approval, is automatically extended for up to 240 days after I-94 expiration when an extension of stay request is filed on time.

Flexibility for Late Applications. USCIS may excuse a nonimmigrant’s failure to timely file an extension/change of status request if the delay was due to extraordinary circumstances. Under current regulations and as noted on our Special Situations page, if a petitioner or applicant files an extension of stay or change of status request (on Forms I-129 or I-539) after the authorized period of admission expires, USCIS may excuse the failure to timely file if it was due to extraordinary circumstances beyond their control, such as those that may be caused by COVID-19. The length of delay must be commensurate with the circumstances. The petitioner or applicant must submit credible evidence to support their request, which USCIS will evaluate in its discretion on a case-by-case basis. These special situations have been used at various times in the past, including for natural disasters and similar crises.

Flexibility for Visa Waiver Entrants. Visa Waiver Program (VWP) entrants are generally not eligible to extend their stay or change status. However, under current regulations, if an emergency (such as COVID-19) prevents the departure of a VWP entrant, USCIS in its discretion may grant up to 30 days to allow for satisfactory departure. Please see 8 CFR 217.3(a). For those VWP entrants already granted satisfactory departure and unable to depart within this 30-day period because of COVID-19 related issues, USCIS has the authority to temporarily provide additional 30-day periods of satisfactory departure. To request satisfactory departure from USCIS, a VWP entrant should call the USCIS Contact Center.

For More Information. Please see 8 CFR 214.1(c)(4) and 8 CFR 248.1(c) for additional information on late requests to extend or change status. In addition, please see our Form I-129 and Form I-539 pages for specific filing and eligibility requirements for extensions and changes of status.

From https://www.uscis.gov/about-us/uscis-response-to-covid-19.