High-stakes assessments are a common feature of many education systems. One argument often made against their use, however, is that they have a negative impact on wellbeing across the education sector, including teachers. We present new evidence on this matter by examining how the Statutory Assessment Tests (SATs) conducted in England's primary schools are linked to how anxious teachers feel about work. Drawing on unique panel data from around 1,000 primary school teachers, we illustrate how the SATs are associated with a short increase in teachers' anxiety levels during the week the tests take place. Yet there is little evidence that those most exposed to the pressures of SATs suffer from especially prolonged periods of high anxiety. We thus conclude that, although there may be other reasons to lower the stakes attached to primary school assessments, the benefits for teachers' anxiety levels are likely to be marginal.