Background Employers are key in supporting stroke survivors to return to work (RTW) but do not always have knowledge/skills or guidance to do so. Objectives To explore employers' needs for provision of post-stroke RTW support. Methods Mixed-methods study. Participants recruited through voluntary response/purposive sampling. Survey of employers investigated stroke knowledge (maximum score: 7), RTW process knowledge (maximum score: 8), and perceived competency for actions supporting RTW (maximum score: 100%). Regression analyses explored relationships between employers' demographic/contextual characteristics and knowledge and perceived competency scores. Interviews with employers explored factors influencing their post-stroke RTW support. Interview data were analyzed using a framework analysis. Survey/interview findings were synthesized with those from a qualitative systematic review. Results Across the survey (n = 50), interviews (n = 7), and review (25 studies), employers' support was influenced by stroke survivors' decisions to disclose stroke-related limitations, employers' knowledge regarding roles/responsibilities, employers' communication skills, and information provided by healthcare. Regression analyses: Human resources/occupational health support was positively associated with stroke knowledge (ss = 2.30, 95% CI 0.36-4.41, p = 0.013) and RTW process knowledge (ss = 5.12, 95% CI 1.80-6.87, p = 0.001). Post-stroke RTW experience was positively associated with stroke knowledge (ss = 1.36, 95% CI 0.46-2.26, p = 0.004) and perceived competency (ss = 31.13, 95% CI 18.40-44.76, p = 0.001). Organization size (i.e. working in a larger organization) was positively associated with RTW process knowledge (ss = 2.96, 95% CI 1.52-4.36, p = <.001). Conclusions Employers' RTW support was influenced by personal and environmental factors; they may benefit from education and guidance on stroke and their roles/responsibilities during the RTW process.