Timely intravenous (IV) to oral antimicrobial switch (IV-oral-switch) is a key antimicrobial stewardship (AMS) strategy. A retrospective audit was undertaken to determine concordance with IV-oral-switch guidelines in the context of a long-standing, tightly regulated AMS program. Data from 107 general medical and surgical patients in an Australian hospital were analysed. Median duration of IV antimicrobial courses before switching to oral therapy was 3 days (interquartile range, 2.25-5.00). Timely IV-oral-switch occurred in 57% (n=61) of patients. The median delay to switching was 0 days (IQR 0 to 1.25). In most courses (92/106, 86.8%), the choice of oral alternative after switching was appropriate. In 45% (47/105) of courses, total duration of therapy (IV plus oral) exceeded the recommended duration by >1.0 day. Excessive IV antimicrobial duration was uncommon at a hospital with a tightly regulated AMS program. Total duration of therapy was identified as an AMS target for improvement.