On March 27, Governor Wolf signed Senate Bill 422, which reschedules Pennsylvania’s primary election from April 28 to June 2 due to the COVID-19 emergency. Voters have the option to vote by mail-in ballot rather than going to their polling place on election day. Mail-in ballot applications will be accepted through Tuesday, May 26, 2020. If a voter has already applied for an absentee or mail-in ballot, they do NOT need to reapply.
Source: Mail-in and Absentee Ballot