Correspondence to

Objective To examine the long-term effects of smoking on labour market outcomes using twin data matched to register-based individual information on earnings. Method Twin data for Finnish men born 1945–1957 was used to remove the shared environmental and genetic factors. The results were subjected to extensive robustness testing. Lifetime cigarette consumption was measured by (cumulative) cigarette pack-years in early adulthood. The average of an individual’s earnings (and, alternatively, taxable income) was measured over a subsequent 15-year period in later adulthood. Results Smokers have lower long-term income and earnings. For example, controlling for the share