Introduction Major socioeconomic differences in mortality are observed in high income countries. While smoking remains one of the major single causes of mortality, its contribution to levels and trends in socioeconomic differences in mortality remain unclear. We present estimates of the contribution of smoking to educational differences in mortality between 1971 and 2005.

Methods Census records linked with death records for all Finns aged 50+ were studied. Smoking attributable mortality is estimated with an indirect method developed by Preston et al that uses lung cancer mortality as a proxy for the impact of smoking on mortality from all other causes.

Results In the early 1970s smoking attributable deaths constituted about 27% of all male deaths above age 50 and 17% in the 2000s; 1% and 4% among women respectively. At age 50 life-expectancy differentials between men with basic vs high education increased from 3.4 to 4.4 years. In the absence of smoking these differences would have been 1.5 and 3.1 years, 60% and 25% less than those observed. Half of the increase in life-expectancy among men with basic education was attributable to smoking. Among women the contribution of smoking to educational differentials in mortality was negligible in the 1970s but increased to about 10% in the early 2000s.

Conclusion Smoking continues to have a major influence on educational differences in mortality among men and its contribution is increasing among women. Anti-smoking efforts can achieve gains in longevity among men and reverse the trend of increasing smoking attributable mortality among women.