The increasing (asymmetrical) interdependence between the European Union (EU) and third countries amidst globalization has increased the importance of the partial adoption of EU norms by non-EU countries. Accordingly, academic studies on external differentiated integration, which is broadly defined as the implementation of certain parts of the EU acquis beyond the borders of the Union, gained importance. Turkey serves as an important case for external differentiated integration studies with its dual role both as a candidate country with a fading membership perspective and as a strategic partner of the EU in various policy areas. In recent years, the EU has placed the transfer of its border management norms at the center of its dialogue with Turkey for the management of irregular migration flows. Accordingly, border management is a very convenient policy area to analyze Turkey’s external differentiated integration with the EU from both conceptual and empirical perspectives. This study analyzes the limits and drivers of Turkey’s external differentiated integration with the EU in the field of border management. It focuses on two key issues in this policy area: the implementation of the Integrated Border Management (IBM) system by Turkey and of the functional cooperation with the European Border and Coast Guard Agency FRONTEX. The theoretical part of the article conceptualizes external differentiated integration and its drivers based on different policy transfer models and literature mapping. In the empirical part, the scope of differentiated integration in the implementation of IBM and cooperation with FRONTEX is examined based on the European Commission Turkey reports. The factors affecting the scope and limits of integration are revealed by utilizing the mapping presented in the theoretical part of the article. The main argument of the article is that while attractive and reliable incentives facilitate Turkey’s integration with the EU in the field of border management, sectoral politicization and high adaptation costs negatively affect the success of external differentiated integration.