To produce a summary of the published evidence of the barriers and facilitators for hospital-based routine HIV testing in high-income countries. Electronic databases were searched for studies, which described the offer of HIV testing to adults attending emergency departments (EDs) and acute medical units (AMUs) in the UK and US, published between 2006 and 2015. Other high-income countries were not included, as their guidelines do not recommend routine testing for HIV. The main outcomes of interest were HIV testing uptake, HIV testing coverage, factors facilitating HIV screening and barriers to HIV testing. Fourteen studies met the pre-defined inclusion criteria and critically appraised using mixed methods appraisal tool (MMAT). HIV testing coverage ranged from 9.7% to 38.3% and 18.7% to 26% while uptake levels were high (70.1-84% and 53-75.4%) in the UK and US, respectively. Operational barriers such as lack of time, the need for training and concerns about giving results and follow-up of HIV positive results, were reported. Patient-specific factors including female sex, old age and low risk perception correlated with refusal of HIV testing. Factors that facilitated the offer of HIV testing were venous sampling (vs. point-of-care tests), commitment of medical staff to HIV testing policy and support from local HIV specialist providers. There are several barriers to routine HIV testing in EDs and AMUs. Many of these stem from staff fears about offering HIV testing due to the perceived lack of knowledge about HIV. Our systematic review highlights areas which can be targeted to increase coverage of routine HIV testing. © 2017 British HIV Association.