English as a lingua franca (ELF) is not only a language of international study, trade and research, but also to a great extent the chosen language of communication in social contexts such as in friendships, families and romantic relationships all over the world. This chapter investigates ELF in the social sphere, concentrating particularly on intimate, long-term relationships. It begins with a literature review on multilingual practices in social ELF and discusses the progress from code-switching to a translanguaging practice that seems to develop in close relationships over time. The chapter describes the pragmatics of pre-empting misunderstandings in long-term ELF relationships, in order to offer a more complete understanding of the nature of ELF in social contexts. It focuses on a previously unpublished investigation into the development of social identities linked to ELF that are formed in established intercultural relationships.