Objective: To provide a rapid clinical update on casemix, average length of stay, and the effectiveness of Australian private psychiatric hospitals. Methods: We conducted a descriptive analysis of the publicly available patient data from the Australian Private Hospitals Association Private Psychiatric Hospitals Data Reporting and Analysis Service website, from 2015–2016 to 2019–2020. This was compared with corresponding reporting on public and private hospitals from the Australian Institute of Health and Welfare, and Australian Mental Health Outcomes and Classification Network. Results: In 2019–2020, there were 72 private psychiatric hospitals in Australia with 3582 acute beds. There were 42,942 inpatients with 1,286,470 days of care, and a mean length of stay 19.6 days (SD 13.9) for the financial year 2019–2020. The main diagnoses were major affective and other mood disorders (49%), and alcohol and other substance abuse disorders (21%). Clinician-rated outcome measures, that is, the HoNOS, showed an improvement effect size of 1.64, while the patient-rated MHQ-14 showed an improvement effect size of 1.18. Results are similar for previous years. Conclusions: Private psychiatric hospitals provide substantial, effective psychiatric care.