The authors describe a long-term audit of outcomes and costs associated with referrals from two established neighbouring school-entry vision screening services in the UK over one academic year with one adhering to national UK screening guidelines more closely than the other. Both services test four- to five-year-old children in the first year of school and use linear logMAR 3m Sonksen tests with pass threshold of 0.2logMAR in either eye. The first service was delivered by five experienced orthoptists. The second was delivered by school nurse services where training is neither orthoptic-led or delivered. The study period was 2018-2019. In the orthoptic service, 5878 children were in the school year of which 5839 were successfully screened (99.3%). Others had special needs and were referred elsewhere, were sick or were from travelling families and therefore deferred to the next school year. Four were untraceable. Recall for a second screen of queries results was for 202 children, who passed at the second screen. Of 199 (3.5%) referred from screening, 48 were lost to first follow-up and a further 11 failed to attend during treatment. One hundred and forty could be followed to discharge. One hundred and thirty-eight of 151 had confirmed reduced vision (91.4% true positive). Overall 79% improved with glasses or spontaneously. Total cost per school test was £4.21 per child. Cost of hospital appointment was £70. Mean cost of glasses voucher was £46.59. Total cost of false positive was £910. Cost for full amblyopia diagnosis was £189.80. Cost per child with confirmed reduced vision was £195.22 and per amblyope was £683.28. For the school nurse service, 5630 were screened and 215 (3.8%) were referred similar to orthoptists. One hundred and seventy were followed to discharge with 83 having confirmed reduced vision with a true positive rate of 48%. The main difference in costs for this service relate to false positive referrals. Cost per child with confirmed reduced vision and seen at hospital was £288.70 (46% more than orthoptists) and per amblyope was £948.09 (39% more). Costs and outcomes were unknown for children referred by school service to local optometrists. Limitations are data availability for the services and this was an audit, although the design was appropriate for an audit with extensive review of the data available. Diagnosis and refractive error were not available. The authors were unable to address specific at-risk groups such as ethnicity and social economic status. The authors conclude the results support the UK national screening model as being highly cost-effective. The key to success is a single accurate screen by experienced screeners at site providing high coverage with possible retest and integrated service from screen to discharge.