One of the features of local-level Europeanization has been the emergence of transnational networking (TN) undertaken by subnational authorities (SNAs). This activity, which received much attention during the 1990s, enables SNAs to take advantage of the opportunities created by European integration. However, empirical analyses of TN are lacking, despite European integration and the wider context SNAs find themselves within evolving. Consequently, little remains understood about how SNAs engage in TN and how they are affected by Europeanization pressures. Using the case of TN undertaken by SNAs in South East England and Northern France, this article finds that Europeanization has created more opportunities for SNAs to engage at the European level. SNAs have, in turn, taken advantage of these opportunities, leading to increased participation in TN. However, SNAs’ approaches to TN are not uniform. Engagement remains marked by differentiation as local-level factors, such as local strategy and political objectives, affect how SNAs participate in TN. This differentiation is likely to become increasingly marked as SNAs respond to contemporary challenges, such as budgetary pressures and, in the case of South East England, Brexit.