Ivy smothers the walls, tree roots push through the stonework, and the interior is so choked with brambles and collapsed tombs that reaching the east window in 2008 required clearing and scrambling. Yet most of the walls survive to near full height, and the west gable, the one elevation largely free of ivy, stands as close to complete as anything built from rubble limestone and sandstone has a right to be after several centuries of neglect. A blocked window opening is still visible about 1.2 metres above the present ground level on that west face, its breach filled at some earlier point with what a nineteenth-century observer called modern mason-work. Thirty metres to the south, a nineteenth-century Church of Ireland building occupies the same graveyard, a quiet illustration of how religious continuity and architectural discontinuity can occupy the same ground simultaneously.

The place name Ballyseedy derives from Bailte Ó Síoda, meaning O'Sheedy's town, and the parish falls within the Diocese of Ardfert, the ancient Kerry bishopric associated with St Brendan. The church appears in the Papal Taxation of 1302 to 1307 as 'Balisida', valued at ten shillings per annum. By 1307 it surfaces in a legal dispute between Philip le Furetter and Hugh de Barry, in which a man named Nicholas O'Molran is described as a felon who had abjured, that is, renounced under oath, the land from within the church of Ballysyd, a reference that points to the medieval practice of claiming sanctuary within a consecrated building. By 1615, a Royal Visitation of the Diocese of Ardfert records a reading minister named Jessy Gilbert serving the vicarage, then valued at £6. When the antiquary Curry visited in 1841, he found the walls nearly perfect and recorded the east window in detail: twin-lighted, divided by a stone mullion, pointed on the outside and formed of brown sandstone and limestone. A survey carried out in 2008 confirmed his description and identified the ogee heads, a decorative curved arch form, carved from limestone, as most likely fifteenth-century work. The mullion survives to full height, though part of its central dividing section is lost, and draw bar sockets remain visible within the splayed embrasure, evidence that the window was once secured against the outside world.