Medicare covers Mohs micrographic surgery when a dermatologist performs it to remove skin cancer, but you pay a share of the cost and the surgery must happen in an outpatient setting.

Mohs surgery is a precise technique for removing skin cancer layer by layer, checking each layer under a microscope before removing the next one. It's most commonly used for basal cell carcinoma and squamous cell carcinoma on the face, ears, and other visible areas where preserving healthy skin matters. Medicare Part B covers the procedure itself when performed by a may have access to dermatologist or other physician, but coverage depends on the cancer being documented and the setting being approved.

You will owe a copay or coinsurance — typically 20 percent of what Medicare allows after you've met your Part B deductible for the year. The exact amount varies based on your specific plan and the facility where the surgery takes place. If you have a Medigap or Medicare Advantage plan, your out-of-pocket cost may be lower, but you need to check your plan documents or call your insurer before the procedure.

Key Takeaways

  • Medicare Part B covers Mohs surgery for skin cancer removal when performed by a may have access to physician in an outpatient setting.
  • You pay 20 percent coinsurance after meeting your annual Part B deductible, unless you have supplemental coverage that reduces your share.
  • The dermatologist's office must be enrolled in Medicare and the cancer diagnosis must be documented for the claim to process.
  • Pathology fees and any reconstruction or closure after the cancer is removed may be billed separately and have their own coverage rules.

How Medicare Determines Coverage for Mohs Surgery

Medicare covers Mohs surgery under Part B as a surgical procedure when the diagnosis is skin cancer — specifically basal cell carcinoma, squamous cell carcinoma, or melanoma. The procedure code Medicare uses is 17311 through 17315, depending on the size and location of the lesion and how many stages the surgeon needs to remove. Your dermatologist or surgeon must be enrolled in Medicare and must document the cancer diagnosis in your medical record before the surgery takes place.

The setting matters. Medicare covers Mohs surgery only when it's performed in an outpatient facility — either the surgeon's office, an ambulatory surgical center, or a hospital outpatient department. If the surgery is done in a hospital inpatient setting, different rules explore and your costs may be different. Most Mohs procedures happen in the dermatologist's office, which is the most common outpatient setting.

Medicare will not cover Mohs surgery for lesions that are not cancer or for cosmetic reasons. If the pathology report later shows the lesion was benign (not cancer), you may be responsible for the full cost of the procedure, so it's important that the diagnosis is confirmed before surgery begins.

What You Pay Out of Pocket

After you meet your Part B deductible (which is $240 in 2024, though this amount changes yearly), you pay 20 percent of the Medicare-approved amount for the Mohs surgery itself. If the approved amount is $1,000, you would owe $200. The dermatologist's office bills Medicare first, and Medicare sends you an Explanation of Benefits (EOB) showing what they paid and what you owe.

Pathology services — the lab work examining the tissue samples — are billed separately and also covered at 80 percent by Medicare. Reconstruction or closure of the wound after the cancer is removed may be coded as a separate procedure and billed separately as well. Each service has its own approved amount, so your total out-of-pocket cost is the sum of your 20 percent shares across all the services provided that day.

If you have a Medigap policy (supplemental insurance), it typically covers the 20 percent coinsurance you would otherwise owe, bringing your cost to zero or close to it. If you have a Medicare Advantage plan, your copay or coinsurance depends on your plan's design — some plans charge a flat copay for surgery, others charge coinsurance. Call your plan before the procedure to find out your exact cost.

Documenting the Diagnosis Before Surgery

Your dermatologist must have a documented diagnosis of skin cancer before performing Mohs surgery for Medicare to cover it. This usually means a biopsy was already done and came back positive for cancer, or the physician has clinical documentation that strongly suggests cancer based on examination. Medicare will ask to see this documentation when the claim is submitted.

If you're having Mohs surgery on a lesion that hasn't been biopsied yet, ask your dermatologist whether they will biopsy it first or whether they plan to proceed with Mohs based on clinical appearance alone. Some dermatologists do a small biopsy in the office before scheduling Mohs; others proceed directly to Mohs if they are highly confident of the diagnosis. Either way, the documentation must be in your chart before the surgery date, or Medicare may deny the claim.

What Happens If Medicare Denies the Claim

If Medicare denies the claim — usually because the diagnosis wasn't documented, the setting wasn't approved, or the procedure code was incorrect — you have the right to appeal. The dermatologist's office should file the appeal on your behalf, but you can also request an appeal yourself by contacting Medicare directly through your state's Medicare Administrative Contractor (MAC).

If you receive a bill from the dermatologist after a denial, do not pay it when ready. Ask the office whether they plan to appeal or whether they will write off the charge. If the denial was due to a documentation error on their end, they may absorb the cost rather than bill you. If the denial was because the procedure truly doesn't meet Medicare's criteria, you may be responsible for the full amount.

Mohs Surgery at Different Types of Facilities

Most Mohs surgery happens in a dermatologist's private office, where the surgeon performs the procedure and the pathology lab is on-site or very close by. This is usually the fastest and most convenient setting, and Medicare covers it the same way — you pay 20 percent coinsurance after your deductible.

Some hospitals and ambulatory surgical centers also offer Mohs surgery. If the procedure is done at a hospital outpatient department, you may owe a facility fee in addition to the surgeon's fee, and your total out-of-pocket cost will be higher. Ambulatory surgical centers typically charge a facility fee as well. Ask your dermatologist where they plan to perform the surgery and whether there will be a separate facility charge before you schedule.

Reconstruction and Closure After Mohs Surgery

After the cancer is removed, the wound must be closed. Sometimes this is a straightforward closure that the Mohs surgeon does as part of the same procedure. Other times, especially on the face or in cosmetically sensitive areas, a plastic surgeon or the dermatologist may perform a more complex reconstruction — a flap, a graft, or a layered closure.

Medicare covers the reconstruction as a separate procedure with its own code and its own 20 percent coinsurance. If a plastic surgeon performs the reconstruction, make sure they are enrolled in Medicare and that the procedure is coded correctly so the claim processes smoothly. Ask your Mohs surgeon before the day of surgery whether they expect to do the closure themselves or refer you to another surgeon, so you know what to expect and can verify coverage with both providers if needed.

Frequently Asked Questions

Will Medicare cover Mohs surgery on my ear or scalp?

Yes, Medicare covers Mohs surgery on any body part where skin cancer is present, including the ear, scalp, nose, and face. The procedure code and your out-of-pocket cost are the same regardless of location. The main difference is that reconstruction may be more complex on the face or ear, which could mean a higher total bill.

What if I haven't met my Part B deductible yet this year?

You will owe the full deductible amount first (up to $240 in 2024), then 20 percent of the Medicare-approved amount for the surgery and related services. If the total approved amount is $1,500, you would owe $240 for the deductible plus 20 percent of the remaining $1,260, which is $252, for a total of $492 out of pocket.

Can I use my Medicare Advantage plan for Mohs surgery?

Yes, Medicare Advantage plans must cover Mohs surgery for skin cancer the same way Original Medicare does. However, your out-of-pocket cost depends on your specific plan — some charge a flat copay for outpatient surgery, others charge coinsurance. Call your plan's customer service number before scheduling to find out what you'll owe.

What if the pathology report shows the lesion was not cancer?

If the final pathology shows the lesion was benign, Medicare may deny the claim because the procedure was not for cancer treatment. You could be billed for the full cost. This is rare, but it's why it's important to have a strong clinical suspicion or a prior biopsy confirming cancer before Mohs surgery begins.

Does Medicare cover Mohs surgery for melanoma?

Yes, Medicare covers Mohs surgery for melanoma, though Mohs is less commonly used for melanoma than for basal cell or squamous cell carcinoma. Your dermatologist or surgeon must document the melanoma diagnosis and perform the procedure in an approved outpatient setting. Coverage and your out-of-pocket cost are the same as for other skin cancers.