This study examined the impact of Pathway Home™ (PH) transition services for high utilizers of psychiatric hospitalization on inpatient days and outpatient engagement post-hospital discharge. This case series study of forty PH graduates (5/22/2015-8/31/2018) used Medicaid claims to assess psychiatric inpatient days-per-month, average proportion of months with psychiatric emergency room, outpatient, and health home care management services. T-tests compared three time periods: the year prior, during, and after enrollment. Graduates had significantly fewer psychiatric inpatient days/month during (M = 1.84, p < 0.001) and after PH enrollment (M = 1.88, p < 0.001) compared to prior to enrollment (M = 7.1), while emergency services were stable. Outpatient visits increased from 45% prior to 76% during enrollment (p < 0.001) and was sustained on follow-up (67%, p = 0.008). A similar pattern emerged for health home services (32%, 60%, and 50%). PH is a promising approach for improving outcomes for high utilizers of psychiatric inpatient services, with sustained impact on follow-up.