Data comprise concentrations of organochlorine insecticides and mercury in sparrowhawk, kestrel and heron livers taken during post mortem from deceased birds of prey sent into the Predatory Bird Monitoring Scheme (PBMS) by the public. The data are presented as micrograms of contaminant per gram of liver tissue (wet weight). The PBMS is a long-term, national monitoring scheme that quantifies the concentrations of contaminants in the livers and eggs of selected species of predatory and fish-eating birds in Britain. Levels of contaminants are monitored to determine variations between species and regions, changes over time and effects on individual birds and their populations. The Scheme is currently funded by CEH, Natural England, the Environment Agency (EA) and the Campaign for Responsible Rodenticide Use (CRRU).