This is a Norman cylindrical tub font, carved from a single block of limestone and left entirely plain. Unlike the very large monumental tubs found elsewhere in Northamptonshire and the Midlands, the Ashby St Ledger example is more modest in diameter and height, reflecting the considerable variation in scale among 11th–12th-century rural fonts.

The basin is deep and thick-walled, with a straightforward vertical profile and no mouldings, arcading, or decorative tooling — an austere Romanesque form typical of smaller village churches at the time. It stands on a low, roughly constructed stone base, probably medieval and built up from re-used blocks to stabilise the bowl.

The tall conical wooden cover, with simple facetted panels and metal fittings, is post-medieval (likely 17th–18th century, with later repairs) and helps emphasise the liturgical focus of the font within the church.

Although unadorned and comparatively small, the font remains an authentic Norman survival, characteristic of the practical, rural Romanesque stonework of the southern Midlands.