The heterodox literature on financial risk has in recent years focused predominantly on how risk is distributed, and on the market instabilities and social inequalities that different risk distributions seed. Typically much less discussed is the constitution of financial risk, which is this article’s concern. Drawing empirical examples from two climate financial instruments, its particular interest is in the changing scale – social, spatial and temporal – of the “risk pools” associated with different financial products: the populations across which the products in question serve to aggregate underlying risk. The article explores how, against a historical backdrop of four decades of scale compression in the shape of risk individualization under neoliberalism, certain novel climate financial products seemingly indicate a contrary stretching of the risk pool. The article critically examines sovereign catastrophe insurance pools and green (climate) bonds, highlighting both the significance of the stretching that they effect but also the tensions and limits apparent in this emergent dynamic.