Medical students, residents and faculty are all capable of holding biases towards stigmatised groups like people experiencing homelessness. This study sought to investigate how the level of training may influence perceptions of homelessness among medical students, residents and faculty. Additionally, we sought to understand how different specialities perceive people experiencing homelessness and whether this changes at various points in a career. The Health Professionals' Attitudes Towards the Homeless Inventory (HPATHI) was administered to medical students, residents and faculty at one institution in the United States. Basic demographics as well as length of time spent in practice were collected in addition to HPATHI responses. A total of 1,141 individuals were invited to complete the survey, including 736 medical students, 214 residents and 191 faculty. Two hundred and ninety individuals participated in the survey and 238 recorded complete responses were analysed for a sample response rate of 238/1141 (20.9%.) Overall perceptions of homelessness across the entire sample were positive and not greatly influenced by the level of training during a medical career. Medical students across classes were largely in agreement and there was a noticeable increase in positive perceptions for students engaged in clinical rotations. However, clinical specialties demonstrated wide variation in perceptions, with the most prominent differences amongst individuals from surgical subspecialties of General Surgery and Obstetrics & Gynaecology. Our study demonstrates the largely favourable attitudes physicians, residents and students have towards people experiencing homelessness with implications for future work to support greater exposure to underserved populations during training. Specialty choice appears to play a larger role in the formation of attitudes towards underserved populations rather than the length of time spent in a particular specialty.