Presenteeism (working while ill) due to mental ill‐health is estimated to be one of the largest economic costs to employers. We seek to investigate the relationship between line manager training in mental health (MH) and presenteeism trends at work. The aim of this study was twofold: (i) to examine the relationship between the provision of a new and emerging workplace MH and wellbeing (MH&WB) initiative – line manager (LM) training in MH – and presenteeism as reported by organizations and (ii) to examine the reasons for presenteeism, and organizational‐level strategies used to action it. To address these questions, we conducted a secondary data analysis using panel data from 7139 firms in England over four time points (2020–2023). Probit regression analysis revealed that organizations offering LM training are less likely to report presenteeism. Our analysis revealed that providing LM training may increase awareness and readiness to tackle presenteeism within the organization, but this does not always translate into actionable strategies. Limitations of the study and recommendations for future research are discussed.