AIMS To investigate the relationships between age at diagnosis of diabetes, age at diabetic eye screening and severity of diabetic retinopathy at first and subsequent screenings in children aged 12 or 13 years. METHODS Data were extracted from four English screening programmes and from the Scottish, Welsh and Northern Irish programmes on all children with diabetes invited for their first and subsequent screening episodes from the age of 12 years. Retinopathy levels at first and subsequent screens, time from diagnosis of diabetes to first screening and age at diagnosis in years were calculated. RESULTS Data were available for 2125 children with diabetes screened for the first time at age 12 or 13 years. In those diagnosed with diabetes at 2 years of age or less, the proportion with retinopathy in one or both eyes was 20% and 11%, respectively, decreasing to 8% and 2% in those diagnosed between 2 and 12 years (P < 0.0001). Only three children (aged 8, 10 and 11 years at diagnosis of diabetes) had images graded with referable retinopathy and, of these, two had non-referable diabetic retinopathy at all subsequent screenings. Of 1703 children with subsequent images, 25 were graded with referable diabetic retinopathy over a mean follow-up of 3.1 years, an incidence rate of 4.7 (95% confidence interval, 3.1-7.0) per 1000 per year. CONCLUSIONS In this large cohort of children, the low prevalence and incidence rates of referable diabetic retinopathy suggest that screening earlier than age 12 is not necessary.