The submandibular salivary glands sit just below the angle of your jawbone, and in many people they can be felt through the skin with gentle pressure. These walnut-sized glands are among the most superficial structures in the neck, tucked between the lower edge of the mandible and the muscles of the floor of the mouth. Whether you notice them at all depends on your body composition, how you press, and whether anything has caused them to swell. The fact that you can feel a soft, movable lump under your jaw does not, on its own, mean something is wrong, but understanding what you are actually touching can save you unnecessary worry or, when the gland genuinely is enlarged, prompt you to get it checked.
Where the Submandibular Glands Sit and Why They Are Palpable
You have two major salivary glands tucked under your jaw, one on each side. Each submandibular gland rests in a small pocket formed by the investing fascia of the neck, wedged between the inner surface of the mandible and the mylohyoid muscle that forms much of the floor of your mouth.1ScienceDirect (Surgery (Oxford)). Anatomy of the salivary glands The gland has a superficial lobe that wraps around the back edge of the mylohyoid and a deeper portion that extends forward beneath it.2Neuroimaging Clinics of North America. Imaging of the Salivary Glands The superficial lobe is what you are most likely touching when you press your fingertips up and inward, just in front of the angle of your jaw. Covering the gland is only a thin sheet of muscle called the platysma and a layer of skin and subcutaneous fat, so in lean individuals the gland can feel surprisingly prominent even when it is perfectly healthy.
By contrast, your parotid glands, which sit in front of and below each ear, are harder to isolate by touch because they are spread across a broader area and partially wrapped around the back of the jawbone. And the sublingual glands, which lie in the floor of the mouth itself, are generally not palpable from the outside at all. So when people say they can “feel a gland” under their jaw, it is almost always the submandibular gland they are noticing.
What a Normal Gland Feels Like
A healthy submandibular gland feels soft to moderately firm, roughly the size and shape of a small walnut, and it moves slightly when you push on it. It should not hurt when you press it. You can sometimes make the gland easier to feel by tilting your head slightly toward the side you are examining, which relaxes the muscles of the neck. The gland is typically most obvious right along the inner border of the mandible, about two finger-widths in front of the angle where the jaw turns upward toward the ear.
In thinner people or those with less subcutaneous fat under the chin, the gland can feel almost like a distinct marble or nodule, which is often what prompts the initial alarm. If you compare both sides and they feel roughly the same size and firmness, and neither one hurts, you are probably just feeling normal anatomy. Dental and medical professionals routinely palpate these glands during head-and-neck exams precisely because they are accessible, and their examination is considered a standard part of assessing any dental patient.3ScienceDirect / Elsevier (Dental Clinics of North America). The Importance of Palpation; The Examination of the Salivary Glands
When Swelling Means Something Is Blocking the Duct
The single most common reason a submandibular gland becomes noticeably swollen is a salivary stone, a small calcium deposit that lodges in Wharton’s duct, the tube that carries saliva from the gland into your mouth. The hallmark symptom is swelling and pain that flares up during meals and then slowly subsides between meals.4Journal of Oral and Maxillofacial Surgery. Submandibular salivary stones: current management modalities This happens because eating stimulates saliva production, and the saliva backs up behind the stone, stretching the gland. Once you stop eating, production slows and the gland gradually deflates.
Stones are usually on one side only, and they range in size from a tiny grain of sand to something the size of a small bean. Most have a rough, irregular surface and a yellowish color. If a stone blocks the duct repeatedly over weeks or months, the gland can develop chronic inflammation and scarring, so some degree of firmness or enlargement may persist even after the stone is removed.4Journal of Oral and Maxillofacial Surgery. Submandibular salivary stones: current management modalities The submandibular gland is especially prone to stones because its duct runs uphill from the gland to the floor of the mouth, and its saliva contains more calcium-rich mucus than the parotid gland produces.
If you notice swelling under your jaw that reliably gets worse when you eat and better when you rest, a salivary stone is high on the list of possibilities. A doctor or dentist can often feel a large stone by pressing along the floor of the mouth, and ultrasound can confirm the diagnosis with high accuracy. One large study found that ultrasound alone correctly identified salivary stones about 95% of the time, and when combined with sialendoscopy, a technique where a tiny camera is threaded into the duct, the detection rate approached 100%.5PubMed. Ultrasound Supplemented by Sialendoscopy: Diagnostic Value in Sialolithiasis
Infections and Inflammation Without a Stone
Salivary glands can swell from infection even when no stone is present. Bacterial sialadenitis, an infection of the gland itself, usually causes sudden, painful swelling on one side along with redness and sometimes pus draining into the mouth from the duct opening. This tends to happen in people who are dehydrated, have recently had surgery, or are on medications that reduce saliva flow, because stagnant saliva creates a breeding ground for bacteria. The treatment is usually antibiotics, fluids, and gentle massage to keep saliva flowing.
Viral infections can also cause salivary gland swelling. Mumps is the classic example, though it primarily affects the parotid glands rather than the submandibular glands. Other viruses, including HIV and some strains of influenza, occasionally cause submandibular enlargement as well. In viral cases the swelling is usually on both sides and resolves as the infection clears.
Autoimmune and Chronic Inflammatory Conditions
Some people develop persistent, firm swelling of the submandibular gland that does not come and go with meals and does not respond to antibiotics. Two conditions worth knowing about are Sjögren syndrome and IgG4-related disease, because both can produce a lump under the jaw that mimics a tumor.
Sjögren syndrome is an autoimmune condition in which the immune system gradually damages the body’s moisture-producing glands, including salivary and tear glands. The submandibular glands may become chronically swollen, and dry mouth is usually a prominent complaint. IgG4-related disease is a less well-known condition in which inflammatory cells infiltrate and scar various organs, and the submandibular gland is one of its favorite targets. When IgG4-related disease affects the submandibular gland, it is sometimes called a Küttner tumor, though “tumor” is a bit misleading because it is not cancer.6PubMed Central. Küttner Tumor: IgG4-Related Disease of the Submandibular Gland The gland becomes rock-hard and enlarged, and the process can affect both sides.7PubMed. Chronic sclerosing sialadenitis (Küttner tumor) is an IgG4-associated disease
Distinguishing between these conditions and each other, and from chronic obstruction, usually requires blood tests and sometimes a biopsy. All three can produce similar changes on imaging and under the microscope, including dense inflammatory infiltrates and scarring.8PubMed. Differential diagnosis of IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis The practical takeaway is that a persistently hard, non-tender lump under the jaw deserves a workup even if it does not hurt.
Tumors of the Submandibular Gland
The word that tends to spike anxiety when someone feels a lump under their jaw is “tumor,” but salivary gland tumors are genuinely uncommon. They account for roughly 3 to 4% of all head and neck tumors, and of those, the majority arise in the parotid gland, not the submandibular gland.9PubMed Central. Pleomorphic Adenoma of the Submandibular Gland: A Case Report The most common salivary gland tumor overall is pleomorphic adenoma, a benign growth that presents as a slow-growing, painless, mobile mass. When it does appear in the submandibular gland, it typically feels like a firm, freely movable lump that has been growing very gradually over months or years, without pain or other symptoms.
Malignant salivary gland tumors are rarer still. They represent about 3 to 7% of head and neck cancers and most often appear in people in their sixties or seventies.10Journal of Cancer Treatment and Research. Current Thinking on Malignant Salivary Gland Neoplasms Unlike the more common cancers of the mouth and throat, specific risk factors for salivary gland malignancies have not been clearly identified. A malignant lump is more likely to be fixed in place rather than freely movable, and it may be associated with numbness, weakness, or pain. But these features are not always present, which is why any new, painless, growing lump under the jaw should be evaluated rather than assumed to be benign.
Non-Inflammatory Enlargement and Metabolic Causes
Not every enlarged salivary gland is inflamed or obstructed. A condition called sialadenosis causes painless, bilateral swelling of the salivary glands without infection, stones, or tumors. Unlike most of the conditions discussed above, sialadenosis primarily affects the parotid glands rather than the submandibular glands, so the swelling appears more in front of the ears than under the jaw. Still, it is worth mentioning because people sometimes confuse the two locations.
The most common triggers for sialadenosis are chronic alcohol use, diabetes, and bulimia.11PubMed. Sialadenosis in a patient with alcoholic fatty liver developing after heavy alcohol drinking In heavy drinkers, the parotid glands can become chronically and symmetrically enlarged, a change that is painless and often more of a cosmetic concern than a medical one.12PubMed. Alcoholic parotid sialadenosis The underlying problem is not inflammation but rather a metabolic disruption in the gland’s secretory cells. If you notice bilateral, painless swelling of the glands in front of your ears rather than under your jaw, and you have one of these risk factors, sialadenosis is a likely explanation.
Drug Reactions and Unusual Triggers
Certain medications and medical procedures can cause sudden salivary gland swelling that resolves once the trigger is removed. One well-documented example is “iodide mumps,” where iodine-containing contrast dye used during imaging or vascular procedures causes acute bilateral swelling near the jaw. In one reported case, a patient developed firm, non-tender swelling on both sides of his jaw about five hours after receiving iodinated contrast during a carotid artery procedure.13PubMed Central. Acute Submandibular Swelling Complicating Arteriography With Iodide Contrast: A Case Report and Literature Review The swelling resolved on its own over the following days. This reaction is uncommon, but if you have recently had a contrast-enhanced scan and develop sudden bilateral gland swelling, it is worth mentioning to your doctor.
Other medications known to occasionally cause salivary gland enlargement include certain antihypertensives, antipsychotics, and antiretrovirals. The mechanism varies but often involves changes in saliva composition or flow rate. In most cases the swelling subsides when the medication is adjusted or discontinued.
How Aging Changes What You Feel
As you get older, the internal structure of your salivary glands changes. The tissue that actually produces saliva is gradually replaced by fat and fibrous tissue. Quantitative studies have found losses of a third or more in the functional tissue of the submandibular gland over the adult lifespan.14Gerodontology. Structure and Function in Aging Human Salivary Glands This does not necessarily mean the gland shrinks in a way you can feel from the outside, but it does mean that the consistency may change. An older adult’s submandibular gland might feel softer or less distinct than a younger person’s, simply because the dense secretory tissue has been partly replaced by fat.
These age-related changes also help explain why dry mouth becomes more common with age, although medications and other health conditions play a bigger role than glandular aging alone. If you are older and notice that your submandibular glands feel less prominent than they used to, that is likely normal. Conversely, a gland that becomes more prominent or firmer with age is worth having examined, because it is moving against the expected trend.
Differences Between Children and Adults
Salivary gland problems in children are less common than in adults but do occur. Stones can develop in children, though they are much rarer. Children are more prone to certain anatomic variations in their salivary ducts, which can predispose them to ranulas, fluid-filled cysts that form in the floor of the mouth. One study found that about 77% of children who developed ranulas had an anatomic variant called Bartholin’s duct connecting the sublingual and submandibular drainage systems, compared to about 46% of adults with the same condition.15PubMed. Are the patients with anatomic variation of the sublingual/Wharton’s duct system predisposed to ranula formation? In a few of these cases, the ranula can extend beneath the mylohyoid muscle and present as a soft swelling in the neck rather than under the tongue, which can look alarming but is a cyst rather than a gland problem.
Viral infections that cause gland swelling, like mumps, are more common in children, although widespread vaccination has made mumps relatively rare in much of the world. If a child complains of swelling under the jaw, the differential includes reactive lymph nodes (by far the most common cause in kids), viral or bacterial sialadenitis, and much less commonly, stones or cysts.
The Role of Ultrasound and When You Need It
If you or your doctor are concerned about a lump under your jaw, the usual first step in imaging is an ultrasound. It is painless, does not involve radiation, and is remarkably good at distinguishing stones, tumors, cysts, and inflammatory changes from normal gland tissue. Across the literature, ultrasound is considered a first-line diagnostic tool for inflammatory and obstructive salivary gland diseases, proving useful in over 90% of cases.16PubMed Central. Ultrasound in Inflammatory and Obstructive Salivary Gland Diseases: Own Experiences and a Review of the Literature More advanced techniques like elastography, which measures tissue stiffness, can help distinguish between benign and potentially malignant masses.
For some conditions, particularly when autoimmune disease or a subtle tumor is suspected, additional workup is needed: blood tests, MRI, fine-needle aspiration biopsy, or a combination. But the vast majority of people who notice a lump under the jaw and turn out to have a routine explanation (normal gland, reactive lymph node, small stone) will get their answer from a physical exam and an ultrasound alone. If you are pressing on the area repeatedly because you are anxious about it, keep in mind that vigorous poking can itself cause mild swelling and tenderness, which then reinforces the worry. A single calm exam by a professional is more informative than repeated self-palpation.
Lymph Nodes vs. Salivary Glands
One of the most common sources of confusion is that the submandibular region is also home to several lymph nodes. These nodes sit in the same general area as the submandibular gland and can swell in response to infections of the teeth, gums, throat, or skin. A swollen lymph node tends to be smaller, rounder, and more distinct than the gland itself, and it often becomes tender and pops up quickly in response to an infection, then shrinks back down over a week or two. The submandibular gland, by contrast, is larger and has a more oblong or irregular feel.
The two can be tricky to distinguish by self-exam alone, especially when a lymph node is sitting right on top of or next to the gland. If you feel something new under your jaw that appeared suddenly and is tender, a reactive lymph node responding to a cold, dental infection, or sore throat is far more likely than a gland problem. If the swelling has been there for weeks, does not hurt, and does not seem to be shrinking, it is more likely the gland itself, and that warrants a professional look.
A useful trick for telling them apart at home: gently massage the area while sipping something sour, like lemon juice. If the lump swells up noticeably in response to the sour taste, you are almost certainly feeling the gland (or a stone blocking it). Lymph nodes do not respond to gustatory stimulation. This is not a substitute for a proper exam, but it can help calm your nerves in the middle of the night when your fingers keep wandering to the spot under your jaw.