Episcopal worship in Castine dates to the 1890s when several women arranged to have services in their homes. By 1900, a stone chapel, designed by Caroline Schenk, was finished, but it was not until 1956 that Trinity became a year around church. In 1998 a parish hall, with a full kitchen and offices on the ground floor, was added to the original structure, and Trinity transitioned from mission status to a parish. The parish hall hosts parish events and is also available for community events like art classes and a bridge group. During the winter attendance is small (30+), but numbers swell to 80 or more with the arrival of the summer residents.
There are several other churches in town. The Roman Catholic Church is located close to Trinity on Perkins Street; the Trinitarian Church (a merger of Congregationalists and Methodists) stands on Main Street while the Unitarian Church, the oldest church structure in this part of Maine, is on the town green.