Green Brand Equity, Claim Type, and the Credibility Route to Green Advertising Effectiveness

ABSTRACT This study examines how green brand equity (GBE) and the benefit emphasized in a green ad claim jointly influence the effectiveness of green advertising on consumer‐based brand equity (CBBE) in the automotive market. Grounded in legitimacy theory and the consumption value framework, a 2 (GBE: high vs. low) × 5 (claim type: neutral, ecological, economic, hedonic, social) experiment was conducted on 807 French car owners, with consumer‐based brand equity measured before and after ad exposure. The main results show that exposure to green advertising improves CBBE of the advertised brand. Additionally, two moderation effects occur. First, ecological claims outperform neutral, economic, and hedonic claims but do not differ from social claims, suggesting that identity‐relevant benefits, rather than ecological content specifically, drive advertising effectiveness. Second, ad exposure is more effective when a brand has high rather than low initial GBE. In addition, a mediation analysis identifies ad credibility as the mechanism through which GBE moderates advertising effectiveness, offering managers guidance on aligning claim design with a brand's existing environmental legitimacy.