Ringing in one ear is called unilateral tinnitus, and it has a wide range of causes, from something as simple as earwax buildup to conditions that need prompt medical attention. When ringing happens in just one ear rather than both, it’s worth paying closer attention. One-sided tinnitus is more likely to have an identifiable, treatable cause than the general ringing many people experience in both ears.
The Most Common Everyday Causes
The simplest explanation for ringing in one ear is earwax blocking the ear canal. When wax builds up enough to fully occlude the canal, it can cause tinnitus, muffled hearing, and a feeling of fullness. The good news: symptoms usually resolve completely once the wax is cleared.
Eustachian tube dysfunction is another frequent culprit. The Eustachian tube connects your middle ear to the back of your throat and is responsible for equalizing pressure. When it gets inflamed or swollen from a cold, sinus infection, allergies, or even acid reflux, negative pressure builds up in the middle ear. This can produce ringing, popping sounds, muffled hearing, and that plugged-up sensation. Flying or driving through elevation changes can trigger it too, since rapid pressure shifts stress the tube’s lining and cause localized swelling that makes it harder to open.
Noise exposure is another common trigger. A loud concert, power tool use, or even a single gunshot near one ear can cause temporary (or sometimes permanent) ringing on that side.
Jaw Problems and Neck Tension
Your jaw joint sits remarkably close to your ear canal, and problems in one can spill into the other. When the temporomandibular joint (TMJ) or the muscles around it are dysfunctional, abnormal signals from that area can increase the firing rate of nerve cells in the brain’s auditory processing centers. This creates a type of ringing called somatic tinnitus.
One hallmark of somatic tinnitus is that it changes. The pitch, volume, or location of the ringing may shift temporarily when you clench your jaw, open your mouth wide, turn your head, or press on tender spots in your neck or jaw muscles. Teeth grinding (bruxism), frequent neck or shoulder pain, and tender trigger points in the muscles around your jaw and upper spine all point toward this type of tinnitus. Because the damage is typically on one side, the ringing tends to appear in the ear on that same side.
Ménière’s Disease
If your ear ringing comes with episodes of vertigo, hearing loss that seems to fluctuate, and a sensation of pressure or fullness in the affected ear, Ménière’s disease is a possibility. It’s a disorder of the inner ear that typically affects one side. The defining feature is recurrent vertigo episodes lasting anywhere from 20 minutes to 12 hours, combined with documented hearing loss in the low-to-mid frequencies on the affected side. The tinnitus, hearing changes, and fullness tend to fluctuate together, often worsening before or during a vertigo attack.
Pulsatile Tinnitus: A Different Kind of Ringing
If the sound in your ear beats in rhythm with your pulse, that’s pulsatile tinnitus, and it has a distinct set of causes. You’re hearing your own blood flow, usually because something is creating turbulence in a nearby blood vessel.
The most common cause is atherosclerotic carotid artery disease, where narrowing of the carotid artery (which runs right past the ear) creates turbulent blood flow you can actually hear. Uncontrolled high blood pressure is another frequent trigger, since elevated pressure increases the force of blood moving through vessels near the ear. Even natural variations in the position of certain arteries near the skull base can produce this sound in people with normal blood pressure and no artery disease.
Less commonly, pulsatile tinnitus can be caused by small vascular tumors near the middle ear or jugular vein, or by a condition called idiopathic intracranial hypertension, which involves elevated pressure of cerebrospinal fluid. That condition is most often seen in younger women and tends to cause pulsatile tinnitus in both ears, along with headaches and vision changes. Because pulsatile tinnitus frequently points to a vascular problem, imaging is recommended in all cases.
Acoustic Neuroma
One reason doctors take one-sided ringing seriously is vestibular schwannoma, commonly called acoustic neuroma. This is a slow-growing, benign tumor on the nerve that connects the inner ear to the brain. About 73% of people with this tumor experience tinnitus, and for roughly one in ten, ringing in one ear is the very first symptom that brings them to a doctor. Because the tumor grows slowly, dizziness is often mild or absent, since the brain has time to compensate. The more typical pattern is gradual hearing loss on one side paired with persistent tinnitus in that ear.
Acoustic neuromas are not common, but they’re the reason guidelines recommend considering an MRI for anyone with unexplained one-sided tinnitus, even when no other neurological symptoms are present.
When Ringing in One Ear Is Urgent
Sudden sensorineural hearing loss is an ear emergency. It presents as a rapid drop in hearing, typically within hours, and is frequently accompanied by tinnitus in the affected ear. Many people describe it as sudden ear blockage rather than obvious hearing loss, which can lead them to dismiss it. Treatment needs to begin within 72 hours of onset. Missing that window greatly reduces the chance of recovering hearing, and delay often results in permanent loss. If you wake up with sudden muffled hearing and ringing in one ear, or it develops over the course of a day, don’t wait to see if it clears up on its own.
What Doctors Check For
When you see a doctor for ringing in one ear, the first step is a hearing test (audiogram). This identifies whether there’s hearing loss, what type it is, and whether it affects one side more than the other. If middle ear problems or Eustachian tube dysfunction are suspected, a tympanometry test can measure how well the eardrum responds to pressure changes.
For one-sided, non-pulsatile tinnitus, an MRI of the internal auditory canal is often recommended to rule out acoustic neuroma and other structural causes, even when no other concerning symptoms are present. If the tinnitus is pulsatile, imaging focuses on blood vessels: an MR angiogram or contrast-enhanced CT scan to look at the arteries and veins of the head and neck. If a bony or middle-ear abnormality is suspected, CT of the temporal bone is the preferred starting point.
What Makes One-Sided Ringing Different
Tinnitus in both ears is extremely common and is most often related to age-related hearing changes, cumulative noise exposure, or medications. It rarely points to a single identifiable problem. One-sided tinnitus is different. It’s more likely to have a specific, diagnosable cause, and that cause is more likely to be something that benefits from treatment. Specialist evaluation is recommended for all cases of unilateral tinnitus, particularly when it’s accompanied by hearing loss, dizziness, or neurological symptoms. Persistent one-sided ringing lasting longer than six months, and all pulsatile tinnitus regardless of duration, also warrant evaluation.