Whilst research has demonstrated the influence of individual and social identities on drinking-related beliefs and behaviours, none evaluates how identities' incompatibilities are associated with mental health, current drinking status nor intentions, and motivations to change drinking behaviour. The current study explored how variability in incompatibilities between the social identities of being a drinker and a Christian related to mental health, alcohol use behaviour, and intentions to change drinking behaviour. A crosssectional online survey (via a recruitment platform, Prolific) recruited n = 180 US resident Christians who drank alcohol (56.4% male, 46.6% female, mean age = 37 years). Increased incompatibility between identities moderated the effect of current Christian identity on drinking change motivations-with the strongest links amongst those with the highest levels of incompatibility. A similar effect was also shown for increasing incompatibility between perceptions of the self as an individual and drinking behaviour (self/drinker incompatibility). The relationship between Christian identity on current drinking behaviour was also shown to be moderated by decreased Christian/drinker identity incompatibility but not self/drinker incompatibility.