OBJECTIVES: This study examines variations in mortality between socio-economic groups due to the pandemic Influenza (H1N1) 2009 virus in England. METHODS: We established a system to identify all deaths related to pandemic (H1N1) 2009 influenza. We collected the postcode of every individual who died, and through this determined the socio-economic deprivation, urban-rural characteristics and region of their residence. Across England, we were therefore able to examine how mortality rates varied by socio-economic group, between urban and rural areas, and between regions. RESULTS: People in the most deprived quintile of England's population had an age and sex-standardised mortality rate three times that experienced by the least deprived quintile (RR = 3.1, 95% CI 2.2-4.4). Mortality was also higher in urban areas than in rural areas (RR = 1.7, 95% CI 1.2-2.3). Mortality rates were similar between regions of the country. CONCLUSION: Tackling socio-economic health inequalities is a central concept within public health, but has not always been a part of emergency preparedness plans. These data demonstrate the opportunity to reduce the overall impact and narrow inequalities by considering socio-economic disparities in future pandemic planning.