Introduction: The World Health Organization (WHO) recommends HIV Counseling and Testing (HCT) in a range of clinical settings. We describe the characteristics of patients diagnosed with HIV on the medical and surgical wards at a tertiary care hospital in Malawi. Methods: Under the universal opt-out HCT protocol we characterized the number of new HIV/AIDS infections and associated clinical features among hospitalized surgical and medical patients diagnosed during the course of admission. Results: All 2985 and 3959 medical and surgical patients, respectively, admitted between April 2012 and January 2013 were screened for HCT. 62% and 89% of medical and surgical patients, respectively, had an unknown status on admission and qualified for testing. Of the patients with an unknown status, a new HIV diagnosis was made in 20% and 7% of medical and surgical patients, respectively. Of the newly diagnosed patients with a CD4 count recorded, 91% and 67% of medical and surgical patients, respectively, had a count less than 350, qualifying for ART by Malawi ART guidelines. Newly HIV-diagnosed medical and surgical patients had an inpatient mortality of 20% and 2%, respectively. Discussion: While newly diagnosed HIV-positive medical patients had high inpatient mortality and higher rates of WHO stage 3 or 4 conditions, surgical patients presented with less advanced HIV, though still meeting ART initiation guidelines. The medical inpatient wards are an obvious choice for implementing voluntary counseling and testing (VCT), but surgical patients present with less advanced disease and starting treatment in this group could result in more years of life gained.