Marion County, Iowa has 78 churches in the Churches List directory, 0 of them verified and 26 with a published website. The 2020 US Religion Census counted 68 congregations and 18,129 adherents across 33 religious bodies in the county. That is 542 adherents per 1,000 residents of its 33,418 people.
| Religious body | Congregations | Adherents | Per 1,000 pop. |
|---|---|---|---|
| Reformed Church in America | 7 | 7,084 | 212.0 |
| United Methodist Church | 11 | 2,358 | 70.6 |
| Catholic Church | 3 | 1,802 | 53.9 |
| Christian Reformed Church in North America | 6 | 1,640 | 49.1 |
| Evangelical Lutheran Church in America | 2 | 713 | 21.3 |
| Non-denominational Christian Churches | 5 | 620 | 18.6 |
| Lutheran Church--Missouri Synod | 2 | 532 | 15.9 |
| Full Gospel Christian Assemblies International | 1 | 530 | 15.9 |
| Christian Churches and Churches of Christ | 3 | 458 | 13.7 |
| United Reformed Churches in North America | 1 | 443 | 13.3 |
| American Baptist Churches in the USA | 2 | 424 | 12.7 |
| Christian Church (Disciples of Christ) | 2 | 409 | 12.2 |
Source: 2020 US Religion Census (Association of Statisticians of American Religious Bodies). Per-1,000 rates divide reported adherents by the county's 2020 Census population (33,418). Largest 12 bodies by adherents shown.
Directory traditions here: Methodist (15) · Reformed Church in America (12) · Christian (7) · Catholic (6) · Baptist Churches (6) · Other Christian Services (5) · United Methodist (4) · Lutheran (4) · Non-Denominational (3) · Evangelical (2)
Directory listings are mapped to Marion County through the US Census Bureau's 2020 ZCTA-to-county relationship file: each ZIP Code Tabulation Area is assigned to the county holding the largest share of its land area, so a small number of churches in ZIP codes that straddle county lines may be attributed to a neighboring county. Congregation and adherent counts come from the 2020 US Religion Census and are reported by the religious bodies themselves. Population is the county's April 2020 decennial-census base from the US Census Bureau's population-estimates program; per-1,000 adherence rates divide reported adherents by that figure. Corrections to any listing go through the corrections page.