Masseter Botox temporarily relaxes the jaw muscles responsible for chewing, clenching and grinding. It may reduce jaw tension or gradually slim a wide lower face. Treatment commonly uses 30 to 60 total units, which at InjectCo works out at roughly $360 to $720. Masseter injection is off-label for every botulinum toxin approved in the United States.
Written by Kiara DeWitt, BSN, RN, CPN. Medically reviewed by Josh Allen, D.O., Medical Director. Last updated August 2026.
Medical disclaimer: This article is for education only and does not replace medical advice. Individual results vary. If you have trouble swallowing or breathing, muscle weakness, drooping eyelids or vision changes after any injection, seek urgent medical care.

Masseter Botox uses botulinum toxin to reduce activity in the large muscles at the sides of the jaw. Patients consider it for gradual jaw slimming, for symptoms linked to clenching and grinding, or for both.
Providers commonly discuss 15 to 30 Botox units per side, although the final amount depends on muscle size, strength, asymmetry and your goal. At InjectCo, the corresponding estimated cost is $360 to $720 at the regular rate, or $270 to $540 for members.
Results develop gradually. Many providers discuss retreatment somewhere between three and six months, but there is no FDA-labeled duration for masseter treatment because the use is off-label. Individual results vary.
Masseter Botox, sometimes called jawtox, involves injecting a neuromodulator into one of the primary muscles used for chewing. The product temporarily reduces muscle contraction. It is the same Botox used elsewhere on the face, placed in a different muscle.
For cosmetic treatment, reduced activity allows an enlarged masseter to decrease in bulk over several weeks. That may make a muscular or square lower face appear narrower. Botox does not remove facial fat and does not change the jawbone.
Other patients pursue treatment for tightness or discomfort associated with clenching and grinding. Reducing muscle activity may lower the force of those habits, but it does not address every cause of jaw pain. Persistent pain, locking, tooth damage or bite changes may need dental or medical assessment. The Mayo Clinic has a plain-language overview of TMJ disorders if you are still working out what is causing your symptoms.
The reasons patients give fall into a few groups. The evidence behind them is not equally strong, so it is worth separating them out.
Masseter treatment is not a cure for any of these, and it is not a substitute for a diagnosis. Individual results vary.
Masseter Botox at InjectCo costs $12 per unit, or $9 per unit for members. Based on a commonly reported range of 30 to 60 total units, that puts an estimated treatment at $360 to $720 at the regular rate, or $270 to $540 for members.
The table below shows how the number of units affects the total.
| Typical units per side | Total units | At $12 per unit | At $9 per unit member rate |
|---|---|---|---|
| 15 units | 30 units | $360 | $270 |
| 20 units | 40 units | $480 | $360 |
| 25 units | 50 units | $600 | $450 |
| 30 units | 60 units | $720 | $540 |
These figures illustrate possible costs. They are not a prescription and not an InjectCo protocol. Larger or stronger masseter muscles may need more units, and the two sides may need different amounts when one muscle is more developed.
Initial and maintenance doses can differ as the muscle changes over time. The final unit count is a clinical decision made at your appointment, after the injector has assessed your anatomy and your goal.
One thing to watch when comparing quotes: Botox units are specific to Botox. They cannot be converted unit for unit against Dysport, Xeomin, Jeuveau, Daxxify or Letybo. A lower price per unit means nothing until you know the product and the number of units.
Whether any of it can be claimed depends on your plan and on how the treatment is coded. We cover that separately in our guide to whether masseter Botox is covered by insurance. Cosmetic treatment is not generally covered.

Review how your muscle size, treatment goal and expected units per side affect the total price.
An earlier version of this article carried six quotations paraphrased from Reddit and Quora. Those were not verified InjectCo patient testimonials and they were not linked to the individual posts, so we have replaced them. What follows describes the recurring themes in public patient forums, including Botox for TMJ reviews, without presenting anonymous comments as direct patient quotations.
Forum users frequently describe a reduction in clenching, grinding or morning jaw tension after treatment. A recurring detail is that they keep scheduling maintenance, because symptoms return as muscle activity recovers.
Less forceful clenching is another common theme. Worth being clear about the limits: neurotoxin does not repair existing tooth damage and does not replace a dentist-prescribed mouthguard where one is still indicated.
Some users report not reaching their preferred result after a first treatment, with things improving after reassessment or a later session. That is a good argument against treating an initial dose as a permanent formula.
Positive cosmetic accounts describe a softer or narrower lower face. Less often mentioned, but reported: reducing the masseter can also reveal cheek hollowing or lower-face laxity, particularly where the face was not suited to further narrowing.
A number of users describe substantial relief from jaw discomfort alongside temporary fatigue when chewing firm foods. Functional improvement and chewing weakness can sit in the same experience.
Most describe the appointment itself as quick and tolerable. The honest negative is also there: some say the change was too subtle, did not last as long as they expected, or did not justify the cost of maintaining it.
Reviews can help you identify common experiences. They cannot determine your candidacy or predict your response, and they are not typical results. Individual results vary.

Masseter Botox is generally well tolerated, but there are a few effects worth knowing about before you book. Most are short lived: tenderness, swelling, bruising, headache, or your jaw feeling tired when you chew. Results can also look uneven when one muscle is stronger than the other or responds differently. Our broader guide covers the side effects of Botox generally.
The risk specific to this muscle is the one almost no page discusses. The risorius helps pull the corner of the mouth outward, and in anatomical studies it overlies part of the masseter in close to all specimens examined. Toxin placed too superficially, or too far forward toward the front edge of the masseter, can reach the risorius and temporarily weaken the smile on that side.
A 2024 review of masseter injection anatomy lists the main complications as paradoxical bulging, inadvertent injection into the risorius, accidental infiltration of the parotid gland, and facial nerve involvement. Careful assessment, depth and placement reduce that risk. They do not eliminate it, and no injector can promise that a smile change will never happen.
Paradoxical masseteric bulging is the other documented effect worth knowing about. It happens when untreated muscle fibers push outward as other portions weaken, and it tends to be noticed while chewing. In a 2024 review of adverse events across 46,250 treated patients, 223 people reported an adverse effect. Every one of those was temporary, although recovery time varied considerably between patients, and paradoxical bulging accounted for the large majority of the reports. If you notice it, have the injector assess it rather than treating it yourself.
Over repeated cycles, the muscle may progressively reduce in bulk. That can produce more narrowing than intended, or make existing skin laxity more visible. The face is worth reassessing before each maintenance treatment instead of automatically repeating the original dose.
General claims about experience are not enough to go on. These questions test how a provider actually thinks about dosing, anatomy and complications. Take them to any clinic, including this one.
You can review the credentials and clinical backgrounds of our injectors before your appointment. A qualified provider will answer all of this directly.

Discuss the proposed product, units per side, placement, expected changes and possible complications before treatment.
Masseter Botox may be appropriate when strong or enlarged jaw muscles are genuinely contributing to the concern. The first job at the appointment is separating muscle-related width from bone structure, facial fat and loose skin, because only one of those responds to neurotoxin.
Potential candidates may have:
New or severe jaw pain should not be treated as a cosmetic problem by default. A dentist or other qualified clinician may need to assess tooth damage, joint problems, locking or changes in the bite first.
Your appointment begins with a review of your health history, medications, previous treatments, symptoms and goals. Your nurse injector examines the masseters at rest and while you clench, comparing the two sides for size and strength.
If treatment is appropriate, the injector explains the product, the proposed units per side, the estimated cost, the placement, the risks and the expected timeline. You can ask questions before deciding whether to go ahead, and you can decide not to.
The injections themselves are usually brief. Temporary soreness or chewing fatigue may follow. Changes in tension often appear before any visible jaw slimming, which develops gradually as the muscle reduces in bulk. Individual results vary.

InjectCo provides masseter Botox at clinics in Colleyville, Plano, Waxahachie, Argyle, The Woodlands, Fort Worth, Dallas, Austin and Cleburne.
Availability varies by clinic and by provider. Select your preferred location when booking so the team can confirm current appointment options.
Cost, dosing and how long masseter Botox lasts are the three things people most want pinned down before booking. The answers below take each one in turn and explain why the numbers shift from one patient to the next.
Masseter Botox at InjectCo is approximately $360 to $720 at the regular rate of $12 per unit. Members paying $9 per unit would spend approximately $270 to $540 for the same illustrative range of 30 to 60 total units.
The final cost depends on the units prescribed after both sides of the jaw are examined. Muscle size, strength, asymmetry, treatment goal and prior response can all move the total.
Providers commonly discuss approximately 15 to 30 Botox units per side, though this is not a fixed protocol. Stronger or larger muscles may need a different amount, and the two sides may not need identical doses.
Units from other neuromodulator brands are not interchangeable with Botox units. Confirm the product before comparing treatment plans or prices.
Many providers discuss retreatment somewhere between three and six months. There is no FDA-labeled duration for masseter treatment, because injecting this muscle is an off-label use.
Duration varies with the product, the dose, muscle activity, metabolism and treatment history. Symptoms and visible jaw width may also return on different timelines. Individual results vary.
No botulinum toxin product is FDA approved specifically for injection into the masseter muscle in the United States. These products carry other approved medical and cosmetic indications, but masseter treatment is an off-label use of an approved product.
Off-label use of an approved product is a different thing from use of an unapproved product. Your provider should identify the product, explain why it is being recommended, and review the risks and alternatives with you.
It can temporarily change the smile if toxin reaches a nearby muscle involved in facial expression. The risorius matters most here, because it overlies part of the masseter in nearly all people examined in anatomical studies.
Careful assessment, dosing, depth and placement can reduce that risk but cannot eliminate it. Contact your injector if you notice smile asymmetry or unexpected weakness.
The effect gradually wears off and masseter activity generally returns. Clenching symptoms may come back, and a slimmer jaw may move toward its earlier shape as the muscle regains bulk.
Stopping does not usually require tapering. Persistent pain, dental damage, locking or bite problems should be assessed rather than managed through repeated injections alone.
Sometimes. Coverage depends on your plan, on whether the treatment is considered medically necessary, and on whether you can show that other treatments were tried without success. Purely cosmetic jaw slimming is not generally covered. We go through the detail in our guide to whether masseter Botox is covered by insurance, and we can help you prepare documentation for a claim.
Masseter Botox can provide meaningful relief from clenching, or a slimmer lower face where enlarged jaw muscles are genuinely driving the concern. The result depends on choosing the right candidate, the right dose and the right injection placement.
Do not make the decision on reviews alone. Before treatment you should know why it suits your anatomy, how many units each side may need, what the full cost will be, and which changes are realistically possible. Individual results vary.

Have a licensed InjectCo nurse injector assess your jaw muscles and explain candidacy, expected units, total cost, risks and likely results.
Dr. Allen earned his Doctor of Osteopathic Medicine at Lake Erie College of Osteopathic Medicine and completed his emergency medicine residency with Texas A&M. As Medical Director, he reviews InjectCo’s treatments, protocols, and patient education content for accuracy and safety across all nine Texas locations.

