The study aims to investigate the impact of brand nostalgia, self-brand connections and parent brand trust on brand extension purchase intention. Additionally, the research examines the moderating effect of brand attachment on the link between brand nostalgia and intention to purchase brand extensions, as well as the relationship between self-brand connections and intention to purchase brand extensions. Design/methodology/approach: The study collected data from 458 respondents in India using a cross-sectional survey research methodology. The collected data were analysed in two stages in SPSS, using structural equation modelling and the process macro bootstrapping method. Findings: The study’s results indicate that although brand nostalgia and self-brand linkages exert a favourable impact on intention to purchase brand extensions, this effect is not significant when it comes to brand trust. Brand attachment acts as a moderator between brand nostalgia and the intention to purchase brand extensions. Additionally, brand attachment acts as a moderator between self-brand connections and the intention to purchase brand extensions. Research limitations/implications: The study adds to the consumer–brand relationship and brand extension literature by proposing and empirically testing a comprehensive model that determines the role of brand nostalgia in the formation of self-brand connections with the brand, trust in the parent brand and, finally, the intention to purchase brand extensions. Additionally, it examines if consumers’ attachment to the parent brand increases or decreases their intention to purchase brand extensions. Practical implications: Consumer brand nostalgia may be leveraged while introducing brand extensions into the market. What is more, managers could use brand attachment to enhance the impact of brand nostalgia for favourable brand expansion assessments. Originality/value: To the best of the authors’ knowledge, this is the first research to examine the influence of brand nostalgia and self-brand connections on the intention to purchase brand extensions. Besides, it tests the moderating impact of brand attachment on the relationship between brand nostalgia and intention to purchase brand extensions.