Purpose Employers are important stakeholders in the return to work (RTW) of employees with cancer. However, it is unclear what employer actions are most important to that process. The objective, therefore, was to reach consensus on what employer actions are considered most important for the RTW of employees with cancer, by employers and employees separately. Methods A two-round online Delphi study was conducted with two expert panels: one with 23 employers and one with 29 employees with cancer. The results from each panel were analysed separately. Out of 24 suggested employer actions, participants selected the 10 they considered most important for RTW in each of the following RTW phases: (1) disclosure, (2) treatment, (3) RTW plan, and (4) actual RTW. The consensus threshold was set at ≥ 80% during the second round. Results The employer and employee expert panels both reached consensus on the importance of 'emotional support', 'practical support', 'allow sufficient sick leave', 'plan return to work', 'adjust expectations', 'assess work ability', and 'show appreciation'. Employers also reached consensus on 'communicate' and 'treat normally', and employees on 'handle unpredictability'. All these employer actions were considered to be specific for one to three RTW phases. Conclusions Employers reached consensus on the importance of nine employer actions, employees on eight. Both stakeholder perspectives showed great similarities, but did vary regarding important employer actions during the employee's treatment. We recommend developing interventions targeting the employer, meeting both employer and employee needs in each RTW phase, to enhance RTW support for employees with cancer.