The aims of this project were to map the location and density of gambling machines in Britain; to explore whether geographic areas with higher densities of machines exist and to examine the socio-economic characteristics of these areas relative to others. Using geospatial analysis of premises records, we identified 8861 Machine Zones which were areas with a 400 meter radius around gambling machine venue and 384 High Density Machine Zones (HDMZ) with 1 or more gambling machine per hectare. There was a significant correlation between machine density and socio-economic deprivation. HDMZs had greater levels of income deprivation, more economically inactive people and a younger age profile than other areas; 37 % of those living in HDMZs were economically inactive compared with 33 % of those in non-machine areas. HDMZs were in seaside locations but also New Towns or satellite towns to major urban areas. Area affluence explains some of this pattern; of the New Towns with HDMZs, 78 % were in New Towns with a high proportion of low income areas. We therefore concluded that the distribution of gambling machines in Great Britain, in line with other international jurisdictions, displays a significant association with areas of socio-economic deprivation. The profile of the resident population living in HDMZs mirrors the profile of those most at-risk of experiencing harm from gambling. This spatial pattern has important implications for assessing the relationship between gambling availability and gambling-related harm, and for the future development of policy, harm-prevention and treatment strategies.