BackgroundMental health in the UK had deteriorated compared with pre-pandemic trends. The impact of COVID-19 on the subjective wellbeing of working populations with distinct lifestyles is not yet studied.MethodsCombining time use surveys collected pre- and during COVID-19, latent class analysis was used to identify distinct lifestyles based on aggregated daily activity patterns and reported working modes. We provide qualitative pen portraits alongside pre-versus-during pandemic comparisons of intraday time use and wellbeing patterns. Lifestyle heterogeneity in wellbeing was quantified in relation to aggregated activity types.ResultsCOVID-19 impact on wellbeing varied significantly between usual working hours (6am-6pm) and rest of the day. The decline in wellbeing outside of usual working hours was significant and consistent across lifestyles. During usual working hours, the direction of impact varied in line with working modes: wellbeing of homeworkers decreased, remained relatively stable for commuters, and increased for certain hybrid workers. Magnitude of impact correlates strongly with lifestyle: those working long and dispersed hours are more sensitive, whereas non-work dominated lifestyles are more resilient.ConclusionThe direction and magnitude of impact from COVID-19 were not uniformly manifested across activity types, time of day, and latent lifestyles. Blurring work-life boundaries and general anxiety about the pandemic may be key determinants of the decline outside of usual working hours. During usual working hours, strong yet complex correlations between wellbeing and time-use changes suggested that policies aiming to enhance wellbeing of workers need to consider not only spatial flexibility but also provide wider support for temporal flexibility.What is already knownIn the UK, mental health deteriorated compared with pre-pandemic trends. It is presumed that not everyone was affected equally, but there has been little evidence distinguishing population groups with distinct working modes and lifestyles.What are the new findingsDirection of COVID-19 impact strongly correlates with working mode and extent of spatial flexibility: wellbeing decreased for homeworkers, but increased for some hybrid workers. Magnitude of COVID-19 impact strongly correlates with lifestyle and extent of temporal flexibility: those working long and dispersed hours more were sensitive, whereas non-work dominated lifestyles were more resilient.How might this impact policyPolicymakers and employers need to consider the important function workplace has on mental health. As homeworking arrangements become permanent, the psychosocial function of traditional workplaces will become more pertinent. Flexibility around the established work-time regime will also benefit workers’ mental health, and give them greater control to choose and transition between lifestyles.