PurposeParticipatory budgeting's (PB’s) proponents hope that bringing development projects to historically underserved communities will improve well-being by extending infrastructure and services. This article details the logic connecting PB to well-being, describes the evolution of PB programs as they spread around the world and consolidates global evidence from research that tests hypotheses on PB's impact. The purpose of this paper is to address these issues.Design/methodology/approachUnstructured literature review and comparative case study across five global regions.FindingsThe authors find evidence for PB's impact on well-being in several important contexts, mostly not only in Brazil, but also in Peru and South Korea. They also find that very few rigorous, large-N, comparative studies have evaluated the relationship between PB and well-being and that the prospects for social accountability and PB's sustainability for well-being are not equally strong in all contexts. They argue that PB has great potential to improve well-being, but program designs, operational rules and supporting local conditions must be favorable to realize that potential.Originality/valueThis is one of the few efforts to build theory on where and why the authors would expect to observe relationships between PB and well-being. It is also one of the first to consolidate global evidence on PB's impact.