The conservation and restoration of existing masonry buildings, many of which are part of the cultural heritage, require strengthening techniques that are minimally invasive, reversible, and compatible with historic substrates. In this context, several studies have demonstrated the effectiveness of Fabric Reinforced Cementitious Matrix (FRCM) composites in confining masonry columns. However, research has predominantly focused on columns made of brick or regular stone blocks, while investigations on the mechanical behaviour of irregular stone masonry columns reinforced with FRCM remain limited. The FRCM system considered in this study consists of unidirectional stainless-steel fibre embedded in a lime-based matrix, applied continuously along the column height. Based on the results of the experimental campaign, this study evaluates the predictive capacity of the formulations currently available in the guidelines, codes and literature to estimate the design axial compression capacity of masonry columns strengthened with different FRCM reinforcement configurations. The results offer valuable insights to optimise FRCM reinforcement strategies tailored for this specific type of masonry, commonly found in vernacular and historic buildings.