Presbyterianism

Presbyterianism is a part of the Reformed tradition of Protestantism, which has its origins to the United Kingdom, particularly Scotland.

Season 4
It is revealed in The Office's season 4 premiere Fun Run, during the discussion about why the employees might have a "curse" put over them, that Pam and Darryl practice the Presbyterian faith. Also in this discussion, we learn that Stanley is Catholic, Phyllis is a Lutheran, Bob Vance is a Unitarian, Kelly is Hindu, Sadiq is a Sikh, and that Creed is a cult leader and follower.

Season 6
Spruce Avenue Presbyterian Church, the church where Jim and Pam get married in "Niagara" is a Presbyterian church, further proving that Pam is a Presbyterian.