The examination of religion within the field of sociology in New Zealand (NZ) is a neglected area of research within academic scholarship. New Zealand is considered a secular society; therefore research examining changes in religiosity has been regarded to have little relevance. New Zealand census data from 2001 to 2018 demonstrates an overall decline in New Zealanders’ religiosity, particularly Christianity, with young adults aged 20 to 30 years demonstrating the greatest decline in affiliation with Christianity. This thesis seeks to examine factors influencing the decline in religious identity/affiliation with Christianity among white/Pākehā New Zealand young adults aged 20 to 30 years. Although researchers, historians and academics acknowledge the religious decline in New Zealand, little research has been conducted within the New Zealand context exploring why young adults are no longer self-identifying with Christianity. This study employed an online survey collecting qualitative and quantitative data. Fifty-two young adults aged 20 to 30 years who had previously self-identified as Christian, and at the time of surveying were no longer affiliated with Christianity responded. Data analysis revealed the overarching theme of cognitive dissonance, the inability to reconcile childhood religious teaching, and their subsequent life experiences, as the primary factor contributing to young adult disaffiliation with Christianity. Cognitive dissonance was demonstrated in three key areas of conflict: moral and political, general church and Christian, and scientific and intellectual. These findings highlight that responded idetitifed these issues as harmful, attributing to their disaffiliation with Christianity. Partiuclarly, respondants identified religious rhetoric with regard to gender roles, purity culture, treatment and judgement of LGBTQI communities, displaying manipulation and judgement, and the disrespect and disregard for scientific teachings as the primary drivers of their discontentment. In conclusion, Christianity was found to be both irrelevant and in conflict with lived experiences. Their life experiences within a secular New Zealand were not able to be reconciled with their religious teachings receive during childhood and within youth based Christian communities on the Christian view morals, science, intellectual thought, biblical and general Christian beliefs, and values. This research explores contemporary experiences of Christianity as it relates to young adults, thus having broader implications for future research seeking to unpack changing social and cultural values among young white/ Pākehā New Zealand populations.