This chapter explores the impact that Brexit will have on Sweden’s participation in the Economic and Monetary Union (EMU), and more specifically on Sweden’s stance towards membership in the European Banking Union, in which Sweden currently has a semi-outsider status. If the EU deepens integration in this area, will Sweden be content to continue on the outside? The chapter focuses on exploring whether and how Sweden is acting to define and secure its preferences regarding any deepening of EMU. Is the Swedish status quo being defended, or is there a will to change it in return for new gains? What drives these calculations and strategies? And in what ways - if any - is domestic political opinion being used or shaped in this process? We draw on primary document analysis and semi-structured elite interviews to set out our case. We do so by using three concepts from historical institutionalism as applied in EU studies: path dependency, unintended consequences, and critical junctures. The chapter concludes that Sweden’s semi-outsider status within EMU will be harder to justify and maintain in the post-Brexit future.