The primary aim of this study was to describe clinical characteristics and natural history of age-related distance esotropia (ARDET) within an adult cohort over a 20-year period. This was a retrospective review of 73 patients from 751 with adult onset strabismus diagnosed with distance esotropia – 9.7% (5.8 per 100,000 residents per year, CI 4.4-7.1). Mean age at presentation was 70 years (range 19-93), greater in females >80% complaining of diplopia. The mean angle of deviation was 7.6PD at distance and 0.4PD for near. Treatment initially was with prisms for 74% and the remainder were observed without treatment. Mean follow-up was 99 months (range 0-312). An increase in angle by >6PD was observed in 23.2%. Almost 10% resolved and 13.7% required surgery. The authors conclude that ARDET affected 1 in 10 new diagnosed cases of adult onset strabismus, is mostly in older females and half with increase in deviation over follow-up. Many have systemic disease such as hypertension and cardiovascular disease.