PURPOSE: To establish the proportion of patients who are blind or have low vision prior to undergoing cataract surgery at tertiary referral centers in Tanzania. To assess which patient groups presenting for cataract surgery are more likely to be blind or visually impaired. METHODS: Using pre-existing computerized audit systems we gathered data on pre-operative visual status, age, gender and presentation mode (walk-in or outreach) for 3765 patients undergoing 4258 cataract operations at 2 hospitals in Tanzania. Visual status was defined based on vision in the better eye. RESULTS: 32% of operations were performed on blind patients, 37% on patients with low vision and 31% on normally sighted patients. Predictors of blindness at presentation were: female sex (OR 1.15; 95% CI 1.00-1.32); referral from a rural outreach program (OR 1.75; 95% CI 1.51-2.02) and older age (OR 1.02; 95% CI 1.01-1.02). CONCLUSIONS: It is not only the blind who present to cataract services in Tanzania. The demand for surgery amongst patients who or are normally sighted represents a positive move towards prevention, and not only cure of cataract blindness in Tanzania. However, it also highlights the need to target those left blind from cataract in order to deliver services to those most in need. Cataract programs targeting patients in rural areas and older patients are likely to increase the number of blind patients benefiting from cataract services.