By the time of the Civil Survey in 1654–6, this once impressive structure was already described as ‘a castle covered with thatch without repaire’, suggesting its fortunes had declined considerably. The castle’s most notable residents were Sir Richard Everard and his wife Catherine Tobin, who married in 1627 and made Ballyboy their home during the 1630s. According to family wills from 1631 and 1633, the couple lived here until around 1641, when Sir Richard received a grant creating ‘The Manor of Everard’s Castle’ in 1639. Shortly after, they departed for their grander new mansion at Burncourt, leaving behind some uncertainty about whether they had actually resided in the castle itself or in a separate thatched house with bawn that once stood nearby.

What remains today is a fascinating architectural puzzle that reveals multiple phases of construction and modification. The hall-house, built from large, roughly cut limestone blocks, has lost its entire south side to quarrying, but the surviving north wall stretches 14 metres long and rises about 4 metres high, with walls an impressive 1.5 metres thick. The northeast and northwest corners feature external semi-circular turrets, though these appear squared from the interior; a defensive design choice common in Irish tower houses. Three corbels on the western half of the north wall mark where the first floor once rested, whilst evidence of later alterations can be seen in two stone vaults that were subsequently inserted, both springing from a central pier added just south of what was likely the main entrance.

The castle’s defensive features are still visible despite centuries of decay: splayed embrasures mark former window positions in the west wall and at first-floor level in the north wall, both now collapsed but still traceable. These openings would have provided light whilst maintaining security, allowing defenders to observe and potentially fire upon approaching threats. The external base-batter, measuring 0.65 metres high and 0.2 metres wide, would have strengthened the walls against undermining whilst deflecting projectiles. Though much reduced from its former glory, Ballyboy Castle remains an evocative remnant of Anglo-Norman influence in Tipperary, its weathered stones bearing witness to the changing fortunes of the families who once called it home.