This cement rendered stone-walled church has a slate hipped roof partially concealed behind a castellated parapet wall extending around the entire building. The plan form is rectangular with a curved western gable and a truncated wing marking the entrance treatment is treated with four pilasters rising the height of the facade to a peaked parapet below the tower. The upper levels of this entrance are marked by three molded medallions between the pilasters and pointed arched windows and head vestibule of the main entrance. The entrance on the north, directly from Market Square is dominated by a square tower, also castellated at it's parapet. Whereas the main facade is punctuated by rectangular windows with head mouldings, the protruding entrance treatment is treated with four pilasters rising the height of the facade to a peaked parapet below the tower. The upper levels of this entrance are marked by three molded medallions between the pilasters and pointed arched windows and head mouldings in contrast to those of the rest of the facade. The interior of the church is characterised by an extensive wooden balcony. However the interior condition is much deteriorated and in need of repair. The exterior maintenance also leaves much to be desired. The church is important in historic terms as well as for it's prime position as the focal point of the main square of the town (notwithstanding the importance of the Castle Rushen which is to one side). The first St Mary's Church was constructed on this site in 1701 to be replaced by Bishop Wilson 125 years later with the present nave which has no west door, no east window and no stained glass. An octagonal lantern tower was replaced in 1912 by the present square structure and the building was extensively restored in 1954. Since visually the building is falling into decay once more it should be listed for preservation for both it's historic and civic significance.


The above description was prepared in justification of the buidling's protection, prior to the development of Registered Building and Conservation Area legislation and regulation.


The structure was placed on the Protected Buildings Register (No 72) in 1984.  All internal fittings were removed leaving only the roof and masonry shell following approval for its conversion to offices in the mid-1980s.