Cognitive impairment is common in first-episode psychosis (FEP); however, the relationship between duration of untreated psychosis (DUP) and neurocognition remains controversial, and no studies have examined the relationship between DUP and social cognition. This study involved secondary data analysis of baseline data from a randomised controlled trial of supported employment; 122 out 146 young people with FEP met inclusion criteria for this study. Results showed that DUP was not associated with neurocognitive or social cognitive performance. Results do not provide support for the neurotoxicity hypothesis of psychosis.