Cochlear implants are available to a broader range of people than most realize. Adults and children with moderate-to-profound sensorineural hearing loss who get limited benefit from hearing aids are the core candidates, but eligibility has expanded significantly in recent years to include people with hearing loss in just one ear, those with partial high-frequency loss, and infants as young as 7 months old. The specific criteria depend on your age, the type and severity of your hearing loss, and how well you currently understand speech with hearing aids.
Adult Candidacy Requirements
For adults 18 and older, the general threshold is a severe-to-profound sensorineural hearing loss, typically meaning your hearing test shows a pure-tone average of 70 decibels or worse. But the hearing test alone doesn’t tell the full story. The deciding factor is usually how well you understand speech while wearing properly fitted hearing aids. Most FDA-approved devices require that you score 50% or less on sentence recognition tests in your best-aided condition. Some devices set that bar at 40%.
These speech tests are done in a sound booth using recorded sentences or single words. You wear your hearing aids and repeat back what you hear. If you’re catching fewer than half the sentences correctly, that’s strong evidence that hearing aids aren’t giving you enough access to speech, and you likely meet the audiological criteria for an implant.
Medicare updated its coverage criteria in 2022, now covering implants for people with moderate-to-profound hearing loss who score 60% or less on sentence recognition tests in the best-aided condition. That’s a meaningful expansion from the old threshold of 30%, which excluded many people who were clearly struggling. Private insurers vary, but many follow FDA labeling or Medicare guidelines.
Children and Infants
Children can receive cochlear implants starting at 7 months of age. The criteria shift depending on how old the child is at the time of implantation. Infants between 7 and 11 months must have profound hearing loss in both ears, defined as a pure-tone average of 90 decibels or worse. For children 12 months to 5 years old, the threshold drops to moderately severe loss in the low frequencies (55 decibels or worse) with severe-to-profound loss in the higher frequencies.
Because young children can’t sit in a booth and repeat sentences, candidacy is measured differently. Audiologists use parent questionnaires and developmental scales that track whether a child is hitting expected milestones for responding to sound and developing listening skills. If a child plateaus or stops progressing with hearing aids, that’s treated as evidence of limited benefit. For infants under 12 months, behavioral hearing test results need to match objective tests like auditory brainstem response measurements to confirm the degree of loss.
All children under 6 must first try appropriately fitted hearing aids for three to six months, unless there’s a medical reason that makes a trial inappropriate. The point of this trial is to document whether hearing aids provide enough access to sound for the child to develop spoken language. If they don’t, the child moves forward in the evaluation process.
Single-Sided Deafness
Until 2019, cochlear implants in the U.S. were essentially limited to people with significant hearing loss in both ears. That changed when the FDA approved implants for single-sided deafness, meaning profound loss in one ear with normal or near-normal hearing in the other. The current criteria define this as a pure-tone average above 80 decibels in the affected ear and 30 decibels or better in the good ear, with word recognition below 5% in the deaf ear. This approval covers individuals 5 years and older.
A related category, asymmetric hearing loss, was approved at the same time. This covers people who have profound loss in one ear and mild-to-moderately-severe loss in the other, with at least a 15-decibel difference between ears. Before these approvals, people with one deaf ear were typically offered routing devices that sent sound from the deaf side to the hearing ear, but those don’t restore the ability to localize sound or hear in noisy environments the way a cochlear implant can.
Hybrid Implants for Partial Hearing Loss
Some people hear low-pitched sounds reasonably well but have severe loss in the high frequencies, making speech sound muffled or unclear. These individuals may qualify for a hybrid (electro-acoustic) cochlear implant, which uses a shorter electrode to stimulate only the high-frequency portion of the inner ear while preserving the natural low-frequency hearing that remains. A small hearing aid component amplifies the low pitches.
The typical profile for a hybrid device is hearing thresholds of 60 to 65 decibels or better through 500 Hz (the low frequencies) combined with 70 decibels or worse at 2,000 Hz and above (the high frequencies). Word recognition scores need to be 60% or less in the implanted ear. This option fills an important gap for people whose hearing loss pattern doesn’t fit traditional implant criteria but who still struggle significantly with speech clarity.
The Hearing Aid Trial
Almost everyone, adult or child, needs to demonstrate that hearing aids aren’t providing adequate benefit before qualifying for an implant. For adults, the standard is a three-to-six-month trial with properly fitted aids, followed by speech recognition testing. “Properly fitted” matters here. If your hearing aids haven’t been programmed to match your specific hearing loss using verified measurements, the results of your speech test may not accurately reflect what amplification can do for you. A cochlear implant center will typically verify your hearing aid settings before testing.
For adults, limited benefit generally means scoring below 40% on a speech-in-quiet test at a conversational volume. Some clinicians also test speech understanding in background noise, where scores below 60% on sentence tests at a moderate noise level can indicate candidacy even when quiet scores are somewhat higher.
Who Doesn’t Qualify
A few conditions rule out cochlear implantation entirely. People born without a cochlea (the spiral-shaped structure in the inner ear) or without a functioning auditory nerve cannot benefit from an implant, because the device works by electrically stimulating that nerve. If the nerve isn’t there, there’s nothing to stimulate. People who cannot safely undergo general anesthesia are also not candidates.
Hearing loss that is conductive, meaning it originates in the outer or middle ear rather than the inner ear, is better treated with other options like bone-anchored hearing devices or surgery to repair the middle ear structures. And if your hearing loss responds well to hearing aids, with good speech understanding, an implant isn’t indicated because it wouldn’t offer a meaningful advantage over what you already have.
A malformed or undersized cochlea, on the other hand, does not automatically disqualify you. Cochlear hypoplasia can make surgery more complex, but it’s not a contraindication.
How Duration of Hearing Loss Affects Outcomes
Candidacy isn’t just about whether you qualify on paper. How long you’ve lived with severe hearing loss before getting an implant has a meaningful effect on how well it works. A meta-analysis covering more than 1,000 patients found a consistent negative relationship between years of deafness and post-implant speech understanding. People who had been deaf for fewer than 5 years tended to recover speech perception more quickly, while those with more than 12 years of profound hearing loss showed notably weaker outcomes. The decline became especially steep beyond 30 years of deafness.
This doesn’t mean long-term deaf individuals can’t benefit. Many do. But the brain’s auditory pathways weaken without input over time, and rebuilding those connections takes longer and may not reach the same ceiling. Researchers describe this as the ratio of time spent deaf versus time spent hearing. The larger the proportion of your life spent without usable hearing, the harder the brain has to work to interpret the electrical signal from an implant. More experience using the implant over time does help offset the effect, but the practical takeaway is clear: if you think you might qualify, earlier evaluation is better than waiting.
What the Evaluation Involves
A cochlear implant evaluation is a multi-step process. It starts with a comprehensive hearing test and speech recognition assessment, both with and without hearing aids. If you meet the audiological criteria, the next step is imaging. A CT scan shows the bony anatomy of the inner ear, including the cochlea’s shape and the surgical landmarks the surgeon needs to plan the approach. An MRI shows the soft tissue: the fluid inside the cochlea, any scarring or fibrosis from prior infections or fractures, and critically, whether the auditory nerve is present and of normal size. Both scans are complementary, and most centers order both.
People with a history of meningitis, temporal bone fracture, or otosclerosis (abnormal bone growth in the ear) get particular attention on imaging, because these conditions can cause scarring inside the cochlea that makes electrode insertion more difficult or affects how well the implant performs. Early fibrosis that looks normal on CT may only show up on MRI, which is why both are important.
Beyond the medical and audiological workup, most programs also include a counseling session to discuss realistic expectations, the commitment to post-operative rehabilitation, and what the listening experience will be like. A cochlear implant doesn’t restore natural hearing. It provides a new way of hearing that takes time and practice to learn, especially for people who have been deaf for many years or who lost hearing before learning to speak.