Abstract Background The COVID-19 crisis has caused profound impact on societal, economic, and healthcare systems. The nature and distribution of these impacts, especially over longer periods of time, is still in need of further investigation. We aim to examine the prevalence of and determinants for poor labour market outcomes during the COVID-19 pandemic among adult workers in the Northern Netherlands. Methods We conducted a longitudinal study based on data from the Lifelines COVID-19 cohort. Data from 23 waves (March 2020 - November 2021) were used. Participants were workers between 18 and 64 years of age (n = 22,378). Dependent variables were labour market outcomes, i.e., unemployment, hours of work, quality of work and sickness absence. Independent variables are sociodemographic and work characteristics, pre-existing health conditions, COVID-19 disease, and government support measures. We employed logistic Generalised Estimating Equations (GEE) to estimate population effects. Results Decrease in hours and quality of work, and requiring sickness absence were markedly present in our sample. While the former seems to show partial recovery throughout the pandemic, the two latter seem to vary over time. The prevalence of unemployment was low. Using GEE, we have found erratic patterns of risk for the four labour market outcomes. Pointing to the vast heterogeneity of experiences and impacts on the labour market outcomes of workers. Women, for example, had higher odds of becoming unemployed (OR: 1.48, 95% CI: 1.23-1.79), but lower odds of decreasing their work hours (OR: 0.90, 95% CI: 0.86-0.93). Discussion The results of this study point to the unequal and heterogeneous impact of the COVID-19 pandemic, as well as the presence of less visible negative outcomes among workers, such as decrease in quality of work. For a complete rebound from this crisis, policy should be aimed at addressing these differential impacts among the population. Key messages • The impact of the COVID-19 pandemic on the labour market is more ...