To adapt pension systems to demographic trends, many countries are reducing pay-as-you-go public pension levels and lifting retirement ages. In this context, funded pensions could play a major role to avoid adequacy gaps. Yet, as this paper shows, the coverage of funded private pensions, as measured by enrolment rates, is highly uneven across countries and between individuals, especially in voluntary systems. Some countries have made funded pensions compulsory (e.g. Australia, Chile) or quasimandatory (e.g. Denmark, the Netherlands) to ensure that most workers are covered and therefore have access to a sufficiently high complementary pension. However, in other countries with relatively low pay-as-you-go public pension benefits, funded private provision remains voluntary. The low level of funded pensions’ coverage in such countries should be a major policy concern. Recent policy initiatives in Germany and New Zealand, involving the introduction of financial incentives (and auto enrolment in New Zealand) have been effective in raising coverage to the highest levels among voluntary pension arrangements, but coverage gaps remain that need to be addressed.