In this article, we analyse the level of and development in students' academic stress due to the COVID-19 pandemic. We devote particular attention to students that first entered university in 2020, 'the COVID cohort', who had fewer opportunities to integrate in ways that theoretically should mitigate the impact of pandemic-induced disruption to their studies. Using four waves of data, collected 2020-2022, we find evidence of both pandemic and cohort effects among Swedish university students (N = 3138). During the pandemic's first year academic stress due to COVID-19 increased regardless of pre-pandemic university experience. The stress, in turn, negatively impacted students' life satisfaction, a factor theoretically linked to key student outcomes like persistence and academic performance but had limited effect on students' long-term optimism. The COVID cohort expressed higher levels of academic stress and experienced a greater drop in life satisfaction compared to the most senior students (3 years or more), but largely overlapped with students with some university experience (1-2 years). These group differences persisted in spring 2022. Finally, we found that the higher levels of pandemic-induced academic stress in the COVID cohort were mitigated by experiences that foster academic and social integration, specifically by teacher support and social cohesion.