Payment and settlement networks typically involve various tiers of intermediation. This paper develops a model of settlement system to study the endogenous structure of tiered settlement networks, and the welfare consequences of clearing agent (CA) failure. We offer two explanations for tiering: private information regarding participant’s credit worthiness and economies of scale in the participation in the settlement system. CAs play a monitoring and cost-saving role in the settlement network. As a result, a failure of a CA can lead to a large and persistent welfare loss to the economy.