According to the data recently released in the 2025 edition of The Official Catholic Directory, the Diocese of Phoenix is now the second largest Catholic diocese in the United States, passing the Archdiocese of New York and the Archdiocese of Chicago. The Official Catholic Directory is published annually by the United States Conference of Catholic Bishops (USCCB).
Per the 2025 publication, the nation’s five largest U.S. dioceses are the Archdiocese of Los Angeles (3.79 million), Diocese of Phoenix (2.01 million), Archdiocese of Chicago (1.95 million), Archdiocese of Boston (1.79 million) and the Archdiocese of Galveston-Houston (1.70 million).
“The diocese collects data through an annual Pastoral Report, which is completed by each parish and submitted every July to report sacramental data. This information is used for the Official Catholic Directory and the Annuario, both of which are reporting publications required of dioceses throughout the United States,” said Dr. Maria Chavira, chancellor and vice moderator of the curia for the Diocese of Phoenix. “This data is reviewed annually by the bishop and his executive team and provides a comprehensive overview of activity within the Diocese of Phoenix.”
The Diocese of Phoenix is the fastest growing diocese in the U.S., increasing by over 500,000 Catholics in the past 10 years alone. The 44,000 square mile diocese consists of 94 parishes, 24 missions, 29 elementary schools, seven high schools, three universities and the Nazareth Seminary. Numbers have flourished recently, with more than 1,300 candidates and catechumens in 2025, a record amount of people joining the Catholic faith through the Order of Christian Initiation of Adults (OCIA) process.
The new report comes on the heels of Pope Leo XIV appointing Msgr. Peter Dai Bui an auxiliary bishop for the Diocese of Phoenix. Announced on Dec. 19, Bishop-elect Bui will be ordained in mid-February, joining Auxiliary Bishop Eduardo Nevares in assisting Bishop John Dolan across the diocese. A priest of the Diocese of Phoenix for over 18 years, Bishop-elect Bui will also continue his role as vicar for clergy.
