The effects of the COVID-19 pandemic on the changing patterns of adversity relative to socioeconomic position were explored in a social study during the first 3 weeks of lockdown in the UK. Data from 12,527 adults, who participated in an online weekly panel as part of the University College London COVID-19 Social Study, were analysed to assess 10 different types of adverse experiences. There were clear inequalities in adverse experiences by socioeconomic position, particularly for adversities relating to finances (e.g. loss of employment and reduced income) and basic needs (e.g. access to food and medications), which did not change over time.