The payments landscape is evolving rapidly, and fast payment systems (FPS) have emerged globally as a key innovation. Jurisdictions differ in their approach to designing FPS and in user adoption. In this paper we lay out the main design features of FPS that may foster adoption based on a novel qualitative and quantitative dataset of FPS in 13 jurisdictions. Cross-country regressions suggest that adoption of fast payments is greater when there are more use cases, more cross-border connections, when non-banks can participate in the FPS and when the public sector plays an active role in the FPS. In addition, we find that implementing an FPS improves financial inclusion, beyond payments.