Through top-down language planning and bottom-up advocacy, the Catalan language has often been presented as a language of societal cohesion in today’s multiethnic and multilingual Catalonia. This article makes informed observations of an ad hoc Catalan language activist collective-No em canviïs la llengua. No em canviïs la llengua points to experiences of “native-born” Catalan interlocutors “changing language” to Castilian with them, and in 2019 created an informal group to express ideological opposition to alleged linguistic discrimination. I interpret No em canviïs la llengua as a novel example of language activism which follows from the historical trajectory of Catalan language policy and the work of other more formally established language organisations in Catalonia. Through their casually organised platform of events and social media interactions, these activists employ familiar rhetoric to construct an ideological narrative about the Catalan language: a “language that unites us”. I use highlights from semi-structured interviews and a brief observational study of a No em canviïs la llengua event in February 2020 to showcase how these activists utilise extant narratives about the Catalan language as a “tool of social cohesion”. I use a metapragmatic analysis to highlight themes of social equality, Catalan speaker identity, and linguistic agency. My analysis supports a non-essentialist approach to framing language activism, expanding beyond explicit demonstrations of activism, formal organisations, or native in-group/indigenous identities. As examples of social action, participation in sociolinguistic debate and interventions in metadiscourse also represent activism as a form of linguistic citizenship.