This chapter deals with the development of the public pension insurance system in Bulgaria during the communist era (1944–1989). The first section focuses on the Communist Party as the main actor in pension policy during the communist era. It discusses the development of the party's programmatic goals, ideological concepts, strategic plans, and decisions that had a decisive influence on the Communist Party's pension policy and thus on the development of the public pension system under communism. The second section provides an overview of the main trends in the development of the public pension system under communist rule. The third section focuses on the three main phases in the development of the pension system during the communist era: the transitional phase (1944–1948), the period of Sovietisation in Bulgaria (1949–1955), and the period from the start of de-Stalinisation in 1956 to the adoption of the last major pension reform in communist Bulgaria in 1975. It addresses the key political and socioeconomic developments in each of these phases and, drawing on archival documents, sheds light on the main motives and legal provisions of the pension legislation adopted. The final section provides a summary of the main findings and draws an interim conclusion.