Largest suffragan dioceses by membership

As of 2026-10-12, Diocese of San Pablo tops the list with 3,052,485 members.

1. #1 Diocese of San Pablo — 3,052,485 members

   diocese of the Catholic Church in the Philippines

   source Wikidata
2. #2 Roman Catholic Diocese of Culiacán — 1,938,677 members

   diocese of the Catholic Church in Mexico

   source Wikidata
3. #3 Roman Catholic Diocese of Porto — 1,871,500 members

   diocese of the Catholic Church in Portugal

   source Wikidata
4. #4 Archdiocese of Galveston–Houston — 1,804,100 members

   Catholic archdiocese in the United States

   source Wikidata
5. #5 Diocese of Rockville Centre — 1,796,000 members

   diocese of the Catholic Church in the United States

   source Wikidata
6. #6 Roman Catholic Diocese of Tabasco — 1,707,269 members

   diocese of the Catholic Church in Mexico

   source Wikidata
7. #7 Roman Catholic Diocese of San Cristóbal de Las Casas — 1,600,000 members

   diocese of the Catholic Church in Mexico

   source Wikidata
8. #8 Diocese of Orange in California — 1,579,000 members

   Catholic diocese in the United States

   source Wikidata
9. #9 Roman Catholic Diocese of Cuernavaca — 1,550,100 members

   diocese of the Catholic Church in Mexico

   source Wikidata
10. #10 Roman Catholic Diocese of Iztapalapa — 1,517,130 members

    Catholic diocese in Mexico

    source Wikidata