Although Zachary Taylor was born into an Episcopalian family and his wife was a devout Episcopalian, he never officially became a communicant (full-fledged adult member) of the Episcopal Church (or any other church).
From: Peter Roberts, "Zachary Taylor" page in "God and Country" section of "Science Resources on the Net" website (http://www.geocities.com/peterroberts.geo/Relig-Politics/ZTaylor.html; viewed 29 November 2005):
Religious Affiliation: EpiscopalianSummary of Religious Views:
Franklin Steiner, in his book The Religious Beliefs of Our Presidents, categorized Taylor among "Presidents Whose Religious Views Are Doubtful."