ObjectivesDiagnosis of rumination syndrome (RS) relies on Rome IV criteria. Oesophageal high‐resolution impedance manometry (HRIM) can objectively demonstrate the episodes of rumination, but its role in the diagnostic pathway is not yet established. We aimed to demonstrate the clinical contribution of this tool for the timely diagnosis of RS and diagnostic work‐up of children with unexplained foregut symptoms deemed to be due to other conditions.MethodsHRIMs performed between 2012 and 2021 were searched to retrieve all diagnoses of RS. Medical records were reviewed for clinical data.ResultsOut of 461 HRIMs performed, 76 children had manometric diagnosis of RS (35 male, median age: 13 years). Of them, 47% were not clinically suspected as the symptoms did not fulfil clinical criteria for RS. The indications for HRIM in these cases were investigation of unexplained foregut symptoms (37%), suspected refractory gastroesophageal reflux disease (8%) and dysphagia (2%). Among all HRIMs performed for investigations of unexplained foregut symptoms (n = 80), 35% demonstrated rumination episodes.ConclusionIdentification of characteristic patterns of rumination on HRIM in children with unexplained foregut symptoms enables the immediate diagnosis of RS. Thus, in situations of diagnostic uncertainty, the use of HRIM at early stages of the diagnostic pathway would reduce unnecessary investigations and treatments.