Not surprisingly, most have been Protestants, with Episcopalians clearly leading the way. But four had no formal religious affiliation, something that would probably be the kiss of death in 21st Century America.
More detail in the table below.
Religion and the Presidency
| Religion | No. of Presidents |
| Baptist | 4 |
| Congregationalist | 1 |
| Disciples of Christ | 3 |
| Dutch Reformed | 2 |
| Episcopalian | 11 |
| Methodst | 3 |
| Presbyterian | 8 |
| Quaker | 2 |
| Roman Catholic | 1 |
| Unitarian | 4 |
| No Formal Affiliation | 4 |