<p>Linguistic insecurity is a socio-psychological phenomenon which refers to speakers’ feelings about their own language or variety as inadequate, inferior, deficient or inaccurate. In a heritage language context where there is a lack of familial support for language, linguistic insecurity can be instrumental in our understanding of language maintenance. In the current study, the linguistic (in)security experienced by heritage speakers of the Pomak language was investigated in the context of language endangerment. Data were collected from twelve participants through semi-structured interviews. A deductive thematic approach was utilized to analyse the Pomak speakers’ responses to pre-set themes. The results show that the experiences of linguistic (in)security and reported language proficiency display differences in terms of age and the language spoken. Most participants reported a sense of insecurity, uneasiness, and lack of confidence when speaking Turkish or Pomak, depending on the context. When it comes to family language practices, failure in inter-generational transmission can be seen as a consequence of the linguistic insecurity experienced. Additionally, schooling in the dominant language was found to have a subtractive effect on heritage language maintenance.</p>