OBJECTIVES The aim of this study was to report a series of patients with far-advanced otosclerosis who were unable to benefit from hearing aids. Among patients with profound hearing loss, it is particularly useful to diagnose far-advanced otosclerosis even if relatively rare, because stapes surgery can improve hearing to a level allowing conventional hearing aid use (sometime the only choice before cochlear implant). MATERIAL AND METHODS We retrospectively reviewed the charts of 7 patients (9 operated ears) in order to highlight diagnostic criteria, surgical indications and results of stapes surgery (stapedectomy or stapedotomy). RESULTS Diagnosis of far-advanced otosclerosis was based on clinical presentation, course of hearing loss, positive family history of otosclerosis, and results of CT scan which was helpful in all the cases. Obliterative otosclerosis was found in 55% of the cases. Success of stapes surgery was observed in 89%, with no significant difference between stapedectomy or stapedotomy. CONCLUSION Although rare, far-advanced otosclerosis must be diagnosed because patients can benefit from stapes surgery (and subsequently fitting of appropriate hearing aids).