Background: Nurse Managers require leadership knowledge and applied competencies to communicate a future-oriented vision, support staff, and lead service change. Evidence from Saudi Arabia also indicates that nurse-manager leadership is related to staff engagement and organizational commitment. Purpose: To examine changes in nurse managers’ visionary leadership knowledge and leadership competency after a Visionary Leadership Education Program (VLEP), and accompanying changes in staff nurses’ evaluations of visionary leadership and staff loyalty. Methods: A one-group, pretest-posttest quasi-experimental study was conducted in a maternity department at a tertiary hospital in Taif, Saudi Arabia. Participants were 35 nurse managers and 255 staff nurses. The four-week VLEP comprised eight interactive sessions. Outcomes were measured before and two weeks after the program using a 20-item knowledge questionnaire, a 17-item competency scale, a 14-item staff evaluation scale, and a 13-item staff loyalty scale. Paired t-tests, Pearson correlations, and multiple linear regression were used. Results: Nurse Managers’ knowledge increased from 10.37 to 15.91 of 20 (t = 12.54, p < .001, dz = 2.12), and competency increased from 41.91 to 59.80 of 68 (t = 17.70, p < .001, dz = 2.99). Staff ratings of visionary leadership and loyalty also increased significantly (both p < .001). Staff-rated visionary leadership was positively correlated with loyalty (r = .677), competency (r = .641), and knowledge (r = .356). Conclusion: The VLEP was associated with substantial improvement in nurse managers’ leadership knowledge and competency, alongside more positive staff perceptions and loyalty. Controlled, multicenter studies with longer follow-up are needed.