This paper explores teachers' anxiety about work at 75 timepoints between October 2019 and July 2022, covering the period before, during and towards the end of the COVID-19 pandemic in England. We find the work-related anxiety of headteachers increased substantially throughout the pandemic -much more so than amongst more junior staff. Female teachers experienced a greater impact than men, particularly amongst those with young children. Differences were also observed in work-related anxiety between independent and state schoolteachers, though only during the first lockdown. We illustrate how providing onsite instruction, live online lessons and working longer hours were all associated with raised levels of work-related anxiety.