Using a Balance Theory framework, we examine the effect of fit (cognitive unit U balance) and consumer attitudes (sentiment relations) among partners within a triadic co-branding partnership (celebrity, brand, and charity) on consumer advertisement attitudes and behavioural intentions. Extending Balance Theory, we distinguish between two types of sentiment imbalance, namely, positively dominated imbalance (attitude towards two of the three partners is positive) and negatively dominated imbalance (attitude towards two of the three partners is negative). The results of Study 1 show that ad-based attitudinal judgements are enhanced when a fit is achieved among the three co-branding partners, resulting in greater likelihood of purchase. The findings from Study 2 show that when negatively dominated imbalance is experienced, negative ad-based attitudes mirror those of a consistent, yet negative sentiment state. Study 2 also illustrates that attitudinal judgements and subsequent purchase intentions are significantly more positive when a negative sentiment is held towards one partner within a triadic co-branding situation (positively dominated sentiment imbalance). The results of our study suggest that brands are able to overcome negative consumer attitudes by pairing with both a celebrity and a charity to which consumers feel positive sentiments, thus creating a positively dominated imbalanced situation and enhancing ad attitudes and behavioural intentions.