This presents the data from the National Asthma and COPD Audit Programme's (NACAP) secondary care adult asthma clinical audit 2018/19. The continuous audit, which captures the process and clinical outcomes of treatment in patients admitted to hospital in England, Scotland and Wales, launched on 1 November 2018. This is the first report post launch of continuous data collection, which presents the results of the cohort of patients that arrived to hospital on or after 1 November 2018, who were admitted to adult hospital services, and discharged by 31 March 2019.