Tresmeer lies within the manor of Werrington, formerly in Devonshire, but is itself also connected with Launceston priory. The Norman church of St Nicholas consists of a nave and a chancel. Until the 19thc, the church had not been altered, except by the addition of a 15thc tower. At that point, due to dilapidation, a complete rebuilding was necessary and was carried out in 1880. Today, the only Romanesque feature is the font, dated to the first half of the 12thc.

Henderson states that the church was founded in the 12thc by St Stephen's priory in Launceston. Later, the Capella de Tresmoore was appropriated to the priory of Tywardreath, but seems to have returned to the prior of St Stephen's in the 14thc.

The font is a very rustic piece; possibly the stonemason was attempting to emulate the font of St Stephen's-by-Launceston in the general shape and the position of the cable moulding. The elephantine rounded triangular base is the font's most idiosyncratic feature.