Hearing loss in one ear: causes and what helps
Hearing loss in one ear is called unilateral or asymmetric hearing loss. Often it is something simple, such as wax or fluid, but it should always be checked, because one-sided loss occasionally has a cause that needs investigating.
When your ears stop matching.
Most hearing loss affects both ears fairly evenly, because the most common causes, ageing and noise, affect both sides. When one ear is clearly worse than the other, the cause is more likely to be something specific to that ear.
Living with one weaker ear has its own challenges. Your brain uses the difference between your two ears to work out where sounds are coming from and to pick out speech in noise. With one ear doing most of the work, it can be hard to tell where a voice is coming from, and busy places become very tiring.
Hearing that drops over hours or days needs to be seen by a doctor the same day.
A full test shows how different your ears are. If the difference is significant, we write to your GP, who may arrange a scan.
Signs your ears are not matching.
A full hearing test measures each ear separately. If there is a clear difference, we explain what it may mean and write to your GP with the results.
Common causes of hearing loss in one ear.
The most common cause, and easily fixed.
Read about earwax build-upMiddle or outer ear infections, and glue ear.
Read about glue earAfter an infection or injury.
Read about perforated eardrumA rapid inner ear loss that needs urgent treatment.
Read about sudden hearing lossAttacks of vertigo with fluctuating hearing in one ear.
Read about Ménière's diseaseRare. A slow-growing, non-cancerous growth on the hearing nerve.
Read about acoustic neuromaWhy one-sided loss is always checked.
When a hearing test shows one ear is significantly worse than the other, and there is no obvious cause such as wax or infection, national guidance recommends a GP referral for further investigation. That usually means an MRI scan to rule out problems with the hearing nerve, such as an acoustic neuroma.
That sounds worrying, but in the large majority of people the scan is normal. It is simply the careful thing to do, and it means you can move on to managing the hearing loss with confidence.
Other things can cause a one-sided loss too, including noise from shooting, where the ear nearer the gun takes more of the blast, and conditions such as otosclerosis and cholesteatoma.
Measure it, explain it, and support it.
Both ears tested separately, so the difference between them is measured accurately.
If the results show a significant one-sided loss, we write to your GP and recommend a referral.
If one ear has a loss and the other is fine, a single hearing aid can bring the two closer together.
If one ear has little useful hearing, a CROS system picks up sound on that side and sends it to the better ear.
Get medical help today if
- The hearing loss came on suddenly, over hours or a few days
- It came with severe dizziness, or followed a head injury
- It came with weakness, numbness or a drooping face (call 999)
Sudden hearing loss is an emergency. Contact your GP or NHS 111 the same day, or go to A&E.
Frequently asked questions.
Usually not. Wax, fluid and infection are the most common causes. But one-sided loss should always be checked, and sudden loss needs medical care the same day.
To rule out rare causes such as an acoustic neuroma, a non-cancerous growth on the hearing nerve. Most scans are normal. It is standard practice for a significant one-sided loss.
Yes. If the poorer ear still has useful hearing, a hearing aid on that side can make a big difference. If it does not, a CROS hearing aid sends sound from that side to your better ear.
Your brain compares the timing and loudness of sound at each ear to locate it. When one ear hears much less, that comparison does not work well.
Yes, especially from shooting or using loud tools on one side. The ear nearer the noise source is usually worse.
Check both ears.
A free 60 minute hearing test in our Birmingham clinic, or a home visit across the West Midlands.
Sudden hearing lossAcoustic neuromaMénière's diseaseHearing aid typesHearing tests
Written and clinically reviewed by our HCPC registered audiologists. Last reviewed: 15 October 2026. This page is general information, not a diagnosis. If you are worried about your hearing or your ears, book an appointment or speak to your GP.