The diocese was established on 15 August 2010, under the order of Catholicos Baselios Mar Thoma Didymos I. Its territory centers on Nilackal, Ranni, and the surrounding hill parishes of Pathanamthitta district.
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.
5 districts, listed alphabetically.