We present an update of the Irish Hydrometric Reference Network (IHRN) of river gauging stations from across the Republic of Ireland that have been deemed suitable for assessing climate-driven changes in high, mean and low flows. Selection criteria, analysis of metadata and historical flows, and stakeholder feedback are applied to identify 51 stations for inclusion in the network. Missing daily data were infilled using a conceptual hydrological model and an Artificial Neural Network. As well as providing a dataset for monitoring and detecting the impact of changing climatic conditions on Irish catchments, the updated IHRN offers utility for assessing extremes of flood and drought and for modelling future flow regimes via climate change impact assessments.