Adapting the propositions and concepts of ethnolinguistic identity theory, the present paper examined the interactive effects of identification with English, interlanguage boundary, and the perceived ethnolinguistic vitality of English on mobilising efforts towards English, and competitive efforts against English as a third language among young Swedish-speaking Finns (N = 299). The question is how individuals who already have access to two languages position themselves towards English, and how their disposition towards English relates to identification with the local languages. The data was collected in two Swedish-language secondary schools and analyzed with moderated moderation analysis. The results indicated that the combined effect of identification, interlanguage boundary and English vitality predicted mobilising efforts towards English but not competitive efforts against English. In addition, identification with the majority language Finnish had an impact on both mobilising and competitive efforts, in a way that higher identification with Finnish decreased mobilising efforts and increased competitive efforts against English, while identification with the minority language Swedish did not have an impact on either strategy.language minorities