•This was a retrospective study of 869 subjects with herpes zoster ophthalmicus.•Ocular involvement occurred in 84.8%.•A total of 51.2% had corneal involvement and 47.6% uveitis.•Permanent vision loss (≤20/50) occurred in 9.6%.•Vision loss was associated with older age, immunosuppression, and uveitis. To determine the rate of moderate and severe vision loss following herpes zoster ophthalmicus (HZO) and to identify associated factors. Retrospective cohort study. All subjects with acute HZO seen at a single center from 2006 to 2016 were included in the study. The primary outcome measure was the proportion of individuals with moderate and/or severe loss of vision following an acute episode of HZO. Secondary outcome measures included causes and factors associated with permanent loss of vision owing to HZO. A total of 869 patients with acute HZO were identified with a median follow-up time of 6.3 years (interquartile range 3.7-8.9 years). Ocular involvement of HZO was diagnosed at or within the first month of presentation in 737 individuals (84.8%). The most common sites of ocular involvement were conjunctivitis (76.1%), followed by keratitis (51.2%) and uveitis (47.6%). Moderate vision loss (≤20/50) secondary to HZO occurred in 83 eyes (9.6%) while severe vision loss (≤20/200) occurred in 31 eyes (3.6%). Causes of loss of vision included corneal scarring (94.0%), corneal perforation (4.8%), and secondary glaucoma (1.2%). Severe vision loss was associated with older age (hazard ratio HR 1.059, P = .001), immunosuppression (HR 3.125, P = .028), poor presenting visual acuity (HR 2.821, P = .002), and uveitis (HR 4.777, P = .004) on multivariate analysis. Among individuals with HZO, approximately 1 in 10 individuals may develop moderate or severe vision loss, primarily owing to corneal scarring. Older age, immunosuppression, and uveitis are associated with severe permanent loss of vision secondary to HZO.