Visual hallucinations, in the absence of psychopathology, remains a challenge for diagnosis in clinicians. Charles Bonnet Syndrome (CBS) is a condition whereby a patient experiences visual hallucinations, with clear insight into their nature; this often occurs in people with varying degrees of vision loss. While acknowledging that these phenomena are illusory, they may still cause significant distress to the patient. As a result, prompt awareness and understanding of the condition is essential. However, CBS remains difficult to diagnose through a lack of an accepted set of criteria; this article will briefly address the concept of visual acuity in its diagnosis, alongside some future recommendations to clinicians.