The eighth World Meeting of Families will take place in September 2015. It's expected to draw hundreds of thousands of visitors.
Philadelphia Archdiocese spokesman Ken Gavin tells The Philadelphia Inquirer that "our planning all along has assumed the presence of the Holy Father."
Pope Benedict XVI announced in 2012 that Philadelphia would host the triennial event. At the time, he said he looked forward to meeting the region's Catholics. He attended the seventh convocation of families in Milan.
Benedict has since retired. Pope Francis' schedule remains unclear.
Traditionally, papal trips abroad are confirmed a few months before the journey.