<p>Genetic diversity underpins the adaptive capacity of crop species, making its conservation essential for food security under increasing environmental change. Taro, a vital staple across the Pacific, is central to regional livelihoods and cultural systems. The world’s largest ex-situ taro (<i>Colocasia esculenta</i>) germplasm collection is maintained at the Centre for Pacific Crops and Trees (CePaCT) in Fiji. To optimise the conservation and use of this resource, we assessed genetic diversity, population structure, and redundancy within the collection using microsatellite markers, genotyping 1217 accessions from CePaCT and additional market and farmer samples from selected Pacific countries. Approximately 43% of the CePaCT collection was identified as duplicate material, indicating a substantial opportunity to streamline the collection. Overall diversity values were low, consistent with the predominantly clonal propagation in taro. Minor differences in diversity were observed among countries, except for some underrepresented regions that may benefit from increased sampling. Most genetic variation occurred within rather than between countries, highlighting the extensive material sharing throughout the region, which maximises diversity at a local level. A weak population structure was detected, yet samples could be grouped into six broad genetic clusters, which are useful for breeding and germplasm curation. Market and farmer samples from Fiji closely matched genotypes already in the collection, whereas Samoan material showed less overlap, reflecting active local breeding and the need for inclusion in the regional collection. These findings provide a foundation for enhancing the efficiency, representativeness, and long-term adaptive capacity of the Pacific taro germplasm collection.</p>