BACKGROUND AND OBJECTIVE: To identify the proportion of patients with retinal vein occlusion (RVO) with loss to follow-up (LTFU) along with potential risk factors after receiving an intravitreal anti-vascular endothelial growth factor (VEGF) injection. PATIENTS AND METHODS: A retrospective review based on billing codes was performed from January 1, 2012, to January 1, 2017. LTFU was defined as no office visit within 12 months following an intravitreal injection. Potential risk factors for LTFU were screened using univariate analysis for inclusion in a final multivariate logistic regression model. RESULTS: A total of 3,400 unique patients with RVO with macular edema met the study inclusion criteria. Of these, 863 patients (25.4%) were LTFU. Rates of LTFU varied based on race / ethnicity, age, RVO type, distance from clinic, insurance status, and regional average adjusted gross income. In the multivariate analysis, patients with LTFU were more likely to be black (odds ratio [OR] = 1.37), Hispanic (OR = 2.37), and living more than 20 miles away from clinic (OR = 1.47). Patients who were 65 to 80 years old (OR = 0.71) and those with branch retinal vein occlusion (OR = 0.70) were less likely to be LTFU. Subgroup analysis showed that patients with baseline visual acuity better than 20/50 were also less likely to be LTFU. CONCLUSIONS: Approximately one in four patients did not return for a year or more after receiving an intravitreal injection for RVO. Given the importance of ongoing therapy to prevent vision loss, these "real-world" findings are of significant concern.