Free Guide to Medicare Coverage for Mohs Surgery

Understanding Mohs Surgery and Why Medicare Coverage Matters

Mohs micrographic surgery is a specialized technique used primarily to remove skin cancer, particularly basal cell carcinoma and squamous cell carcinoma. During the procedure, a dermatologist removes thin layers of skin one at a time, examining each layer under a microscope to check for cancer cells. This layer-by-layer approach allows the surgeon to remove all cancerous tissue while preserving as much healthy skin as possible. The procedure is often performed on the face, ears, nose, and other areas where saving skin is especially important for appearance and function.

The American Academy of Dermatology notes that Mohs surgery has cure rates exceeding 99% for newly diagnosed skin cancers and 94% for recurrent cases. This high success rate, combined with tissue preservation, makes it the gold standard treatment for many skin cancers, particularly those in cosmetically or functionally sensitive areas. A typical Mohs surgery procedure can take several hours because of the time needed for microscopic examination between removal stages.

Medicare is a federal health insurance program for people age 65 and older, some younger people with disabilities, and people with end-stage renal disease. Because skin cancer is common in older adults, many Medicare beneficiaries undergo Mohs surgery each year. Understanding how Medicare covers this procedure helps patients plan for medical costs and know what out-of-pocket expenses to expect.

The cost of Mohs surgery without insurance can range from $1,500 to $3,500 or more, depending on the size and location of the lesion and the number of stages required. With Medicare coverage, beneficiaries typically pay a portion of the cost through copayments, coinsurance, and deductibles, rather than the full amount. Knowing these details in advance allows for better financial preparation and informed conversations with healthcare providers.

Practical Takeaway: Mohs surgery is a common, highly effective treatment for skin cancer covered by Medicare. Understanding the basics of the procedure and how coverage works helps you prepare for treatment and anticipate costs.

How Medicare Part B Covers Mohs Surgery

Medicare Part B covers outpatient medical services, including surgeon fees, facility costs, and pathology services related to Mohs surgery. When you have Mohs surgery performed at an outpatient clinic or surgery center, Part B typically covers the surgeon's fee for the procedure itself. The pathology component—the laboratory work examining tissue samples under the microscope—is also covered as a separate service. This is important because Mohs surgery involves multiple tissue examinations, and each examination layer may be billed as a distinct pathology service.

Medicare assigns specific procedure codes to Mohs surgery based on the number of stages (tissue removal layers) required. The codes are: 17311 for the first stage, 17312 for each additional stage up to five stages, and 17313 for stages six and beyond. The surgeon's office submits a claim to Medicare indicating which code applies based on the complexity of the case. Medicare then pays approximately 80% of the approved amount for each code, with you responsible for the remaining 20% coinsurance after your deductible is met.

If you have Original Medicare (Part A and Part B), you will pay the Part B deductible first. For 2024, the Part B deductible is $240 per year. Once you meet this deductible, Medicare covers 80% of the approved amount for Mohs surgery services, and you pay the remaining 20%. If your surgeon's office is a participating Medicare provider, the approved amount is set by Medicare's fee schedule. If the provider is non-participating, your costs may be higher.

The facility where the surgery takes place also files a separate claim for facility fees, which includes use of the operating room or procedure room, equipment, and staff support. This facility fee is also covered at 80% by Medicare Part B after your deductible. Some facilities charge more than others, so it is worth asking about expected facility costs when scheduling your procedure.

Practical Takeaway: Medicare Part B covers most of the cost of Mohs surgery, but you pay 20% coinsurance plus any deductible not yet met. Ask your surgeon's office for an estimate based on expected procedure complexity.

Managing Out-of-Pocket Costs and Deductibles

Your actual out-of-pocket cost for Mohs surgery depends on several factors: whether you have already met your Part B deductible for the year, whether your surgeon is a Medicare-participating provider, and whether you have supplemental insurance. The Part B deductible applies once per calendar year. If you have already had other Part B services earlier in the year (such as office visits, lab work, or imaging), you may have already paid part or all of your deductible. Checking your Medicare Summary Notice or calling Medicare at 1-800-MEDICARE can confirm your deductible status.

For a hypothetical Mohs surgery case, assume the approved amount is $2,000 for surgeon fees and $800 for facility fees, totaling $2,800. If you have not yet met your deductible, you pay the full $240 deductible first. Then Medicare covers 80% of the remaining $2,560 ($2,048), and you pay 20% ($512). Your total out-of-pocket cost would be $752. If you had already met your deductible, you would owe only $560 (20% of $2,800).

Medigap supplemental insurance policies can significantly reduce your out-of-pocket costs. Medigap plans are sold by private insurance companies and are designed to cover costs that Original Medicare does not, including coinsurance and deductibles. For example, a Medigap Plan C or Plan F would cover your 20% coinsurance on Mohs surgery, meaning Medicare pays 80% and your Medigap plan pays the remaining 20%. You would owe only your monthly Medigap premium, with no additional cost for the procedure itself. However, Medigap premiums vary by age, location, and plan type and can range from $100 to $300+ per month.

If you are enrolled in a Medicare Advantage plan (Part C) instead of Original Medicare, your Mohs surgery coverage works differently. Medicare Advantage plans are required to cover all services that Original Medicare covers, but they may have different deductibles, copayments, and coinsurance amounts. Some plans cover Mohs surgery with just a copay (for example, $50 to $150), while others use coinsurance. Review your plan's summary of coverage to understand your specific costs.

Practical Takeaway: Calculate your expected out-of-pocket costs by checking whether you have met your deductible and asking your provider for their Medicare-approved amounts. Consider whether supplemental insurance or a Medicare Advantage plan would reduce your costs.

Finding Medicare-Participating Dermatologists and Facilities

Using a Medicare-participating provider is important because it ensures you pay only the Medicare-approved amount for services. Participating providers have agreed to accept Medicare's approved amount as full payment for covered services. You pay only your deductible and coinsurance based on that approved amount. If you use a non-participating provider, Medicare may still cover part of the cost, but the provider can charge more than the approved amount, and you may owe the difference.

To find a Medicare-participating dermatologist who performs Mohs surgery, you can search the Medicare Provider Enrollment, Chain, and Ownership System (PECOS) database on the CMS website. You can search by provider name, location, or specialty. Alternatively, you can call 1-800-MEDICARE and provide your zip code and the type of provider you are seeking. Medicare representatives can give you a list of participating dermatologists in your area. Many dermatology practices also list their Medicare participation status on their websites.

When you contact a dermatology office, ask whether they perform Mohs surgery in-house or refer patients to another facility. Some dermatologists have on-site Mohs surgery capability, while others work with a dermatologic surgery center or hospital outpatient department. Facilities also participate in Medicare, and you can verify participation using the same PECOS database. In-house surgery may be more convenient and may have lower facility fees than a hospital-based facility, but this varies by location and practice.

Before scheduling your procedure, ask the dermatologist's office about their typical number of stages for the type of skin