In marketing literature, brand promises are commonly defined as concise expressions of a brand’s value proposition and are considered strategic communication tools linking brand identity with consumer perception. However, the increasing intensity of marketing communications driven by digitalization, social media interactions, and multiple consumer touchpoints has significantly expanded the scope and ambition of brand promises. This development has raised new concerns regarding the credibility of such promises. Contemporary consumers approach marketing messages with a more critical perspective and tend to evaluate brand promises not only at the message level but also in terms of their consistency with actual brand experiences and supporting evidence. This study conceptualizes the credibility of brand promises not as a linear increase in trust but as a threshold-based perceptual process. In this context, the concept of the Credibility Threshold in Brand Promises (CTBP) is proposed to explain the critical point at which brand promises shift from generating trust to triggering skepticism and resistance in consumers’ minds. The study examines the role of brand promises in consumer perception through three core functions: expectation formation, signaling meaning and trust, and reducing perceived risk. In addition, structural factors such as signal saturation in marketing communication, increasing persuasion awareness among consumers, and the fragility of trust mechanisms are discussed as key drivers of credibility erosion. By emphasizing that brand promises are evaluated not only by their strength but also by their intensity, contextual relevance, and verifiability, this study aims to provide a conceptual contribution to the marketing literature.