The literature has shown that, in developing countries, large cash transfers to older people improve the wellbeing of the recipients and their families. While social pensions have recently emerged in East Asia to deliver small cash benefits to older people, there is little consistent evidence of their effects. We examine the effects of the Basic Pension Scheme, a social pension in South Korea, on income and consumption poverty among older adults. We apply a difference-in-differences event study design and other complementary approaches to data covering the full period of program development from 2006 to 2021. The results show that the social pension decreases income poverty but not consumption poverty. While this study analysed the best data currently available, using better-quality data in future research would enable more robust analysis. Further research is also warranted to find how to improve the effectiveness of a non-contributory pension programme as a tool for reducing income and consumption poverty among older adults.