BackgroundEustachian tube dysfunction is regarded as a ‘black box’ term, reflecting a spectrum of dysfunction. The key to its diagnosis and management is in identifying the aetiology and exact pathophysiology of the dysfunction.DesignWe present our retrospective 5‐year results for the technique of transnasal endoscopic balloon dilatation of the cartilaginous part of the Eustachian tube, balloon Eustachian tuboplasty (BET). The indication for treatment is chronic obstructive Eustachian tube dysfunction.Main outcome measuresPreoperatively, the Eustachian tube score (ETS) was obtained by a clinico‐objective assessment involving tubomanometry (TMM) and reported patient symptom. The measurements were repeated 1, 2, 3, 4 and 5 years postoperatively.SettingTertiary referral centre.ParticipantsA total of 622 patients (1076 ears) were treated with BET.ResultsOne year after treatment, the Eustachian tube score improved from 3.13 (± 2.47 SD) to 5.75 (± 2.76 SD). The Eustachian tube score improved significantly in 73% of ears. The average Eustachian tube score 2 years after treatment improved from 2.65 (± 2.89 SD) to 6.26 (± 3.07 SD). In 82% of patients, the Eustachian tube score improved significantly at 5 years. The subjective satisfaction of the patients was approximately 80%.ConclusionsOur long‐term results suggest that BET is a safe and feasible treatment for chronic obstructive Eustachian tube dysfunction with a success rate of more than 70%. This study has important implications for other Eustachian tube‐related clinical entities, such as glue ear management (adults and children), continued grommet insertion and tympanomastoid surgery outcomes.