One of the oldest structured dioceses of the Church, Kollam traces its roots to St. Thomas and to the Persian saints Mar Sabor and Mar Proth, and was constituted in 1877.
Counts above reflect Orthodox-held institutions only; churches, chapels, and other properties currently under schismatic occupation are catalogued separately below and are not included in these totals.
Tradition holds that St. Thomas the Apostle, arriving in India in 52 CE, established one of his seven churches at Kalyanapuri (Kollam). Kollam later became a flourishing centre of West Syrian Christian tradition, strengthened in 825 CE by the arrival of the Persian merchant-saints Mar Sabor and Mar Proth, who received royal privileges and land from the local ruler to build the celebrated Tharissapally (Tarisa Church).
The Diocese of Kollam was constituted in 1877 by the Synod of Veliyanad, convened under Patriarch Ignatius Peter IV, making it one of the oldest structured dioceses of the Malankara Church. Its early oversight was led by Geevarghese Mar Gregorios (Parumala Thirumeni), followed by its first official Metropolitan, Dionysius V (Joseph Mar Dionysius). Major territorial changes in 2002 and 2010 subdivided the diocese to form the dioceses of Thiruvananthapuram, Mavelikara, Adoor–Kadampanad and Kottarakkara–Punalur, in order to serve the growing faithful more effectively.
7 districts, listed alphabetically.