PurposeNational data from the United Kingdom reported in 2016 have suggested that almost one quarter of babies with anorectal malformation (ARM) have a delay in diagnosis. The UK’s Newborn Infant Physical Examination dictates a perineal examination should be performed within 72 h of birth. We sought to describe a tertiary single-centre experience of late presentation in the most recent 5 years.MethodsA single-centre prospective registry of ARM patients (July 2018–March 2024) was analysed. Timing of presentation with anomaly was noted. Patients presenting > 72 h or having been discharged home were defined as a delayed diagnosis. Factors associated with delayed diagnosis were noted.ResultsSixty patients were included, of whom nine (15%) were diagnosed after 72 h [range 4–279 days]. This represents a non-significant improvement compared to 39/174 (22%) late diagnosed cases in the BAPS-CASS cohort from 2016 to 17 (p = 0.188). Presenting symptoms of obstruction (i.e. distension, vomiting, megarectum) were more common in late diagnosed patients (4/9 (44%) vs. 1/51(2%); p = 0.001). Anomalies producing meconium on the perineum were more likely to be diagnosed late (8/32 (25%) vs 1/28 (4%); p = 0.029). Complications and changes to clinical management for these cases are presented.ConclusionAlthough our regional rates of late diagnosis appear to be lower than previously reported national rates, there remains a significant number of infants who are diagnosed late especially those with visible perineal openings. These infants are more commonly symptomatic; entraining additional risks associated with an emergency presentation.