For reintroduction programs to succeed, it is vital to identify suitable release sites. This is especially true for low dispersing habitat specialists, which are at particular risk from habitat fragmentation. The habitat specialist Muscardinus avellanarius (hazel dormouse) is part of a large-scale reintroduction program in the UK. The program began in 1993 and has so far had varying levels of long-term success across 24 sites. Although the causes of population persistence at reintroduction sites are not well understood, continued habitat suitability is hypothesized to play an important role. Here, we establish broad-scale habitat descriptors associated with the current distribution of natural hazel dormouse populations in England, using ecological niche factor analysis and remotely sensed, open-source maps. We also apply generalized linear mixed effects models to long-term monitoring data for reintroduced hazel dormouse populations, revealing that broad-scale habitat factors strongly influence the number of animals present in nest boxes. To aid conservation practitioners in future site selection, we illustrate the practical application of habitat suitability mapping to help prioritize the most appropriate woodlands for future hazel dormouse reintroductions, using the county of Cheshire as an example. Although demonstrated here for the hazel dormouse, this approach to reintroduction site selection could be beneficial to a broad range of species