Aim: Crowded logMAR Kay’s pictures is a commonly used vision test in children and our aim was to establish the normative uniocular mean, test/re-test and inter-ocular visual acuity data for this test. Methods: This was a prospective study on a visually normal paediatric population aged 3–4 years. Normative vision values were collected using the crowded logMAR Kay’s pictures test, from children who passed their primary vision screening check. Results: Mean vision data were collected on 110 participants, test/re-test data for 39 participants and inter-ocular acuity data for 38 participants. The overall mean vision value was 0.108 (95% CI ± 0.012, SD 0.062); clinically this mean equates to 0.100 (6/7.5 Snellen’s equivalent). The coefficient of reliability for the test/re-test difference was 0.122; indicating ≥5 pictures difference was significant. The coefficient of reliability for the inter-ocular difference was 0.133; indicating a ≥6 pictures difference was significant. Conclusion: Normative vision data have been produced for clinicians using the crowded logMAR Kay’s pictures vision test in 3- to 4-year-olds.