Richard Stockton was a Presbyterian.
He was identified as a Presbyterian by the Presbyterian Historical Society and the Presbyterian Church, USA. (Source: Ian Dorion, "Table of the Religious Affiliations of American Founders", 1997).
From: Robert G. Ferris (editor), Signers of the Declaration: Historic Places Commemorating the Signing of the Declaration of Independence, published by the United States Department of the Interior, National Park Service: Washington, D.C. (revised edition 1975), pages 134-135:
Like his father a patron of the College of New Jersey, in 1766 Stockton sailed on its behalf to Scotland to recruit Rev. John Witherspoon for the presidency...
...he died at Princeton in 1781 at the age of 50. He is buried at the Stony Brook Quaker Meeting House Cemetery.
Note that numerous sources and authoritative references have been consulted in order to ascertain the religious affiliation of the American Founding Fathers. Note that the excerpts and references mentioned on this page are not the only references used in order to identify this person's religious affiliation.