New Zealand census mortality data from 1981 to 2001 were analysed for any change in disparities between income and mortality during a period of major structural and macroeconomic reform and for how different diseases contributed to these disparities. All-cause mortality rates declined over the 25-year study period in all groups stratified by sex, age, and income, except for 25–44 year olds of both sexes on low incomes among whom there was little change. In all age groups pooled, relative inequalities increased from 1981–4 to 1996–9, then stabilised in 2001–4. Absolute inequalities were stable over time, with a possible fall from 1996–9 to 2001–4. Cardiovascular disease was the major contributor to the observed disparities between income and mortality, but decreased from 45% in 1981–4 to 33% in 2001–4 for males and from 50% to 29% for females. A corresponding increase in cancer occurred; from 16% to 22% for males and from 12% to 25% for females.
