Adopting a mentalist approach to the study of language attitudes, social prestige and stigma, as well as the values and stereotypes bestowed on Sardinian and Italian and their speakers were studied for the first time in Sardinia using the Matched-Guise Technique. The experiment was administered to Sardinian students of different ages, from different parts of the island, with different degrees of Italian/Sardinian bilingualism. Results show that Sardinian speakers are more favourably perceived in terms of friendliness and social pleasantness. Both Italian and Sardinian speakers, with no statistical difference between them, received moderately positive evaluations in traits related to socio-economic and cultural status, suggesting a decline in the traditional negative stereotypes associated with minority language speakers. Moreover, participants’ self-reported use and competence of languages, as well as their amount of school activities involving Sardinian, turned out to interact with the attitudes towards the minority language, as higher values of those variables were associated with higher ratings for Sardinian speakers. Findings could be useful to policy-makers in efforts to maintain Sardinia’s multilingual repertoire, and, more generally, to the scientific community in understanding the patterns and most relevant factors that affect language attitudes in bilingual contexts involving an endangered minority language.