Background. Appropriate antimicrobial use is imperative owing to the misuse of antimicrobials, which has resulted in a growing burden of antimicrobial resistance. Evidence-based guidelines should be adhered to in order to ensure the sustainability of effective antimicrobials. Objectives. To assess the appropriateness of antimicrobial prescribing at a private hospital in Durban, KwaZulu-Natal, South Africa. Methods. The records of patients admitted to the surgical and medical wards over a 2-month period were reviewed to assess the choice, dose and duration of prescribed antimicrobials. The guidelines used to determine the appropriateness of the prescriptions were: the Standard Treatment Guidelines and Essential Medicines List for South Africa -Hospital Level Adults, 2015 edition, the antimicrobial indications and prescribing instructions in the South African Medicines Formulary, the South African Antibiotic Stewardship Programme guidelines and the evidence-based surgical prophylaxis guidelines adopted by the hospital group where the research was conducted. Results. During the study period, 466 patients were admitted and prescribed an antimicrobial, of whom 220 (47.2%) were admitted to the surgical ward and 246 (52.8%) to the medical wards. A total of 779 antimicrobials were prescribed. Of the 660 antimicrobials prescribed for empirical treatment, 305 (46.2%) were appropriately prescribed based on drug choice, dose and duration. Of the 38 antimicrobials that were classified as targeted, 36 (94.7%) were prescribed at the correct dose and 33 (86.8%) for the correct duration. Of the 81 antimicrobials prescribed for surgical prophylaxis, only 32 (39.5%) met the criteria for appropriateness in terms of drug choice, dose and duration. Conclusions. Our findings suggest that compliance with evidence-based guidelines for the use of antimicrobials is not optimal in hospitals in the private sector. Antimicrobials are prescribed inappropriately for empirical treatment and for surgical prophylaxis. Private hospital groups should consider adopting antimicrobial prescribing guidelines that are mandatory for doctors to adhere to in order to promote rational antimicrobial prescribing, and thereby reduce the burden of antimicrobial resistance.