•IT outsourcing (ITO) dynamic capabilities affect ITO success via IT reconfiguration.•ITO dynamic capabilities affect ITO success via IT service delivery.•ITO contract management capabilities affect ITO success via IT service delivery.•ITO relational capabilities affect ITO success via IT service delivery. This study proposes and tests a model of information technology outsourcing (ITO) capabilities as antecedents of ITO success. Building on the dynamic capabilities perspective (DCP), the model posits that ITO sensing, ITO seizing, and ITO orchestrating capabilities will influence ITO success by way of both successful reconfiguration of IT solutions and successful delivery of IT services. Building on extant ITO research, the model also hypothesizes that contract management capabilities and relationship management capabilities will influence ITO success via the successful delivery of IT services. Data from a cross-sectional survey of 152 large U.S.-based organizations in various industries were analyzed with PLS. The results support the hypothesis that successful reconfiguration mediates the effect of dynamic capabilities on ITO success. They partially support the hypothesis of successful delivery as mediator of the effect of dynamic capabilities on ITO success. The hypothesis of successful delivery as a mediator of the effect of relationship management capabilities and contract management capabilities on ITO success is supported only for relationship management capabilities. The study offers a theoretical anchoring for the conceptualization of ITO capabilities, which complements the rich and context-specific case-based literature of ITO capabilities and extends current research by adding to existing explanations of how ITO success is achieved.