PurposeThe emergence of digital health interventions for mental ill-health in the workplace is expansive. Digital interventions delivered in male-dominated settings are less so. This pilot study aimed to assess the usability, feasibility, acceptability, and preliminary effects of an online intervention in a male-dominated organization. We focus on male-dominated as mental ill-health is frequently unrecognized and underdiagnosed among males.MethodsUnwind, a 7-week internet-based program with stress-management components, was tested in a pre-post pilot study. Unwind gets users to identify and understand their stress triggers and assists them to develop adaptive ways to manage these and their stress. Participants were Australian adults employed in a mining company. Follow-up assessment occurred 8 weeks after baseline. The primary outcome measure was change in stress symptoms, with secondary outcomes; change in depression, anxiety, insomnia, well-being, and alcohol use. User feedback and program data were analyzed to assess usability, engagement, and intervention adherence.ResultsEligible participantsn= 87 showed significant reductions in stress (g= 0.46,p< 0.001), depression (g= 0.47,p< 0.001), anxiety (g= 0.50,p< 0.001), insomnia (g= 0.44,p< 0.001), and well-being (g= 0.32,p= 0.004) post-intervention. Significant improvements were observed in both well and unwell (mental ill-health) and male and female participants. There was no gender effect on outcomes. A dose–response was observed as the number of modules used was related positively to improvement in anxiety (F1,86= 5.735,p= 0.019;R2= 0.25). Overall users rated Unwind as useful and engaging.ConclusionThis study presents evidence base that Unwind is a feasible and acceptable approach to reducing employees’ mental health-related symptoms in typically difficult-to-reach male-dominated industries. Unwind is feasible for larger scale delivery within male-dominated industries.