<p>This paper examines the tax treatment of pensioners in 15 industrialised countries. Using a standard methodology, it calculates the average and marginal tax rates of older people and compares them with those of people of working age. These are then combined with a model of pension entitlements in different countries. This shows that tax differentials play an important role in old-age support. We discuss the appropriate way for the tax system to support pensioners and the implications for the tax treatment of private pensions. </p>