Background: Research on geographic acculturation has demonstrated an association between the sort of acculturation strategy adopted by migrants and their mental health status. However, there have been no studies of the relationship between temporal acculturation - attempts to adapt to change within the same society over time - and mental health. Method: We explored the relevance of Berry’s bidimensional framework of acculturation, to perceptions of social change within Ireland over the last 10 years, in a sample of 735 members of the general public. Results: There was a significant relationship between temporal acculturation strategy and mental health. An acculturation strategy of assimilating into ‘modern’ Ireland was associated with significantly better mental health than an ambivalent acculturation strategy. Conclusions: This is a first exploration of the relationship between temporal acculturation and mental health. While models of geographic acculturation are relevant to temporal acculturation, we have also identified a new category of acculturation strategy, ambivalence, as being associated with the poorest mental health outcomes.