We present the first assessment of microbial cell discharge from sediment-laden glacier basal ice. At Svínafellsjökull, a temperate valley glacier in Iceland, approximately 10 17 cells a −1 are transferred through basal ice to the proglacial environment, and between 10 1 and 10 6 cells g −1 basal ice were cultured from our samples under laboratory conditions. We suggest that the delivery of viable cells and dead microbial matter to proglacial ecosystems could be playing a crucial role in soil formation and primary succession during deglaciation, but further quantification of cell transfer from a range of glacier contexts is required.