The building is densely smothered in ivy, poorly preserved, and sits on the north-west edge of an irregularly shaped graveyard at the southern end of a low hill. Below it, a small stream feeds into a turlough, one of those seasonally flooding limestone lakes particular to the west of Ireland that appear and vanish with the water table. The church itself is a modest nave and chancel structure, roughly 19 metres long and just 4.5 metres wide, but its apparent simplicity conceals centuries of rebuilding, patching, and reuse.

The earliest surviving fabric is the east gable, which dates to the late 12th or early 13th century. Its lower courses are battered, meaning they slope outward at the base for structural stability, and they include a dressed stone with diagonal tooling still in its original position on the external face. Inside, at the south end of the same gable, there is an aumbry, a small recessed cupboard set into the wall that would once have held sacred vessels. Around the late 15th or early 16th century, the church was substantially remodelled: much of the east gable was demolished and rebuilt, a squat two-light ogee-headed window was inserted, and the south wall was either reconstructed or built anew, incorporating an ogee-headed doorway and two narrow single-light windows. An ogee arch, with its double S-curve profile, is characteristic of late medieval Irish ecclesiastical stonework. A double water stoup, used for holy water, survives on the west side of that doorway. The west gable, which still stands to its full height and contains a single-light pointed window high up, appears to represent a third phase of work, datable to the late 16th or early 17th century; several dressed stones from the earlier phases were recycled into its fabric. The north wall, meanwhile, was largely intact until 1988, when its upper five or six courses were demolished. The resulting rubble was left in the adjacent field.

Architectural fragments from the church have found a secondary life as grave-markers in the surrounding graveyard, where burials run from the late medieval period through to the 20th century. About 30 metres to the west lies a souterrain, an underground stone-built passage associated with early medieval settlement, suggesting that this corner of Killora was in use long before the first courses of the church were ever laid.