Primary care physicians can play a key role in supporting patients after behavioural weight loss, though little is known about communication between patients and physicians during this time. Adults (n=139) in a behavioural weight loss trial (delivered outside of primary care) who attended a primary care appointment after an initial weight loss period were surveyed to assess weight-related communication at their most recent appointment. Most participants (78%) reported discussing weight with their physician. Participants who discussed weight, compared to those who did not, lost more weight, had higher blood pressure, and were more likely to be male. Most (89%) reported that their physician was supportive of their weight loss, but only a few participants (6.9%) reported that their physician gave feedback on medical parameters. Areas for improvement identified include physicians providing universal support for modest weight changes and providing interpretation of medical measurements that changed due to weight loss.