OBJECTIVE The Spring 2020 UK COVID-19 lockdown required normally-office-based workers to modify their work-related practices to work at home. This study explored workers' experiences of adapting to home-working, health behaviours and wellbeing. METHODS Twenty-seven home-working employees (19 female; aged 23-57y), from various industry sectors, gave individual semi-structured interviews. Topics focused on home-working experiences, routine adaptations, and changes in health behaviours and wellbeing. RESULTS Four themes were extracted: changes to the work interface; adaptations to a new workspace; changes to work-life balance; and adjustments to a new social context. Notably, participants reported greater reliance on computer-based interactions, which they felt discouraged physical activity and increased sitting. Working in a domestic environment reportedly challenged work-home boundaries. CONCLUSIONS Work practices can incidentally detrimentally impact health-related behaviours and wellbeing. Organisations should develop policies and procedures to promote health-conducive home-working.