What survives is the stump of what was once a taller pillar stone, its top broken off and lost at some unknown point, leaving only a small cluster of scored notches along one edge. Those notches are ogham, an early Irish writing system that uses a series of lines and notches cut along the edge or face of a stone to represent letters, most commonly recording a person's name and ancestry. What the full inscription once said is impossible to know. The scholar R. A. S. Macalister, who catalogued it in 1945, could only make out the partial reading VI[R], the remainder gone with the missing upper section.

The stone was first noted in published form by J. G. A. Prim in 1854, who recorded it as standing close to the south wall of the church and roughly nine paces from the round tower nearby. That proximity is worth pausing on. Tullaherin is an early church site of some complexity, with a medieval nave-and-chancel church, a round tower, and not one but two ogham stones. Round towers, tall slender structures built from around the ninth century onwards, are associated with monastic settlements across Ireland, and their presence alongside ogham stones, which generally predate them by several centuries, suggests a site that was in continuous religious use across a considerable span of time. The stone itself is modest in size, measuring roughly 0.7 metres tall and just over half a metre wide, and it stands upright in the graveyard on the south side of the nave.

The graveyard at Tullaherin remains accessible, and the stone sits in plain view close to the church's southern wall towards the western end. Visitors who know to look for the angled scores along the stone's edge, rather than expecting any grand carved face, are more likely to appreciate what they are seeing. The site's second ogham stone is also present in the vicinity, making Tullaherin quietly unusual even among early ecclesiastical sites in the county.