Intentions to act unethically in the workplace are purported to be driven by a number of situational and individual factors. Across two seminal vignette experiments, Jones and Kavanagh reported inconsistent effect sizes for manager and peer influence and locus of control, consistent significant effects for work quality and Machiavellianism, and consistent non-significant effects for gender. Using an innovative multi-site collaboration, the current Registered Report represents a direct replication of these experiments (N = 2218), and adds a longitudinal conceptual replication capturing self-reported unethical work behaviour (N = 1747). Both replications found a consistent small effect of having a more external locus of control and male identity, and a consistent moderate effect of machiavellianism, for increasing unethical intentions and behaviour. The situational factors, whilst consistent in direction with that of the original study, varied more substantively in effect size. Our results highlight the value of multi-site collaborations and different replication types in developing conceptual, methodological, measurement and theoretical clarity to ensure future works can progress more rapidly to minimize the negative impacts of unethical workplace behaviour and improve individual’s working lives. All materials, code and data for this project can be found here: osf.io/d3arx.