OBJECTIVE: To assess the impact of socio-economic status (SES) on cancer survival in the state of New South Wales (NSW), Australia. METHODS: Patients diagnosed with one of 13 major cancers during 1992-2000 in NSW were followed-up to the end of 2001. The effect of SES on survival was estimated for each individual cancer and all 13 cancers combined using multivariable modeling. The numbers of lives that could be extended if all people had the same level of excess risk of death due to cancer as patients in the highest SES areas were also estimated. RESULTS: There were highly statistically significant variations in survival across SES groups for four cancers: stomach, liver, lung, and breast and all 13 cancers combined. Variation remained highly significant after adjusting for disease stage. Patients in lower SES areas had 10-20% higher excess risk than those in the highest SES areas. In total, there were 3,346 lives potentially extendable beyond 5 years; the highest number was for lung cancer (756). CONCLUSION: The significantly worse survival in lower SES areas from cancers of the stomach, liver, lung, and breast may be due to poorer access to high-quality cancer care. Estimates of the number of lives potentially extendable by improving cancer survival in lower SES areas suggest that priority should be given to improving lung cancer care in lower SES areas in NSW, Australia.