Does Medicare Cover Knee Replacement Surgery?

Does Medicare cover knee replacement surgery? Yes — Medicare provides substantial coverage for knee replacement when it is medically necessary. Total and partial knee replacements are among the most common major procedures performed on Medicare beneficiaries, and understanding the coverage details, 2026 costs, and recovery expectations can help you plan with confidence.

According to the Agency for Healthcare Research and Quality (AHRQ), well over 700,000 knee replacements are performed in the United States each year, with the majority of patients over 65. As the population ages, that number keeps climbing. Medicare’s coverage helps ensure that beneficiaries with debilitating knee arthritis can access this life-changing procedure. For a closer look at the price tag itself, see our guide on knee replacement surgery cost.

What Medicare Covers for Knee Replacement

Medicare coverage for knee replacement spans multiple parts of the program, and which part applies depends heavily on whether your surgery is inpatient or outpatient (more on that below).

Medicare Part A (Hospital Insurance) — applies when you are formally admitted as an inpatient:

• Inpatient hospital stay for the surgery
• Semi-private room and board
• Nursing care during the hospital stay
• Meals and medications administered during hospitalization
• Operating room and recovery room costs
• The prosthetic knee implant itself (as part of the inpatient stay)

Medicare Part B (Medical Insurance) — applies to outpatient surgery and to physician and outpatient services regardless of setting:

• Surgeon’s fees for the procedure
• Anesthesia services
• The procedure and facility fee when the surgery is performed on an outpatient basis (hospital outpatient department or ambulatory surgery center)
• Pre-operative consultations and medical clearance
• Diagnostic imaging (X-rays, MRIs) needed to plan surgery
• Post-operative follow-up visits with the surgeon
• Outpatient physical therapy and rehabilitation
• Durable medical equipment (DME) such as a walker, crutches, or knee brace

Medicare Part A (Skilled Nursing Facility): If you need inpatient rehabilitation after surgery, Part A may cover a skilled nursing facility (SNF) stay for up to 100 days — but only following a qualifying inpatient hospital stay of three or more days. This qualifying-stay rule is exactly why the inpatient-vs-outpatient distinction matters so much.

Out-of-Pocket Costs for Knee Replacement (2026)

While Medicare covers knee replacement, beneficiaries are responsible for standard cost-sharing. The 2026 Original Medicare figures are:

• Part A deductible: $1,736 per benefit period (2026), covering the first 60 days of an inpatient hospital stay.
• Hospital coinsurance: $0 per day for days 1-60. For a longer stay, coinsurance is $434 per day for days 61-90, and $868 per day for lifetime-reserve days (91 and beyond) in 2026.
• Part B costs: After the annual Part B deductible ($283 in 2026), you pay 20% of the Medicare-approved amount for surgeon fees, anesthesia, outpatient surgery, outpatient therapy, and DME. There is no annual out-of-pocket cap under Original Medicare, which is a key reason many people add supplemental coverage.
• SNF coinsurance: Days 1-20 in a skilled nursing facility have $0 coinsurance. Days 21-100 require coinsurance of $217 per day (2026).

The total billed cost of a knee replacement (hospital or facility, surgeon, anesthesia, implant, rehabilitation) commonly runs from roughly $30,000 to $60,000 or more depending on the facility, geographic location, and complexity — though what Medicare actually pays, and what you owe, is based on Medicare-approved amounts, not the sticker price. Your out-of-pocket share under Original Medicare alone — after the Part A deductible or Part B deductible plus 20% coinsurance — could range from a couple of thousand dollars to considerably more without supplemental coverage. Estimates vary widely by case; confirm your specifics with your provider and verify current figures at Medicare.gov.

Medigap plans can sharply reduce these costs. A Plan G Medigap policy, for example, covers the Part A deductible, hospital coinsurance, and the 20% Part B coinsurance, leaving you responsible mainly for the annual Part B deductible.

Inpatient vs. Outpatient Knee Replacement

One of the most important — and most misunderstood — aspects of Medicare coverage is whether your knee replacement is classified as inpatient or outpatient:

• Inpatient: You are formally admitted to the hospital. Coverage falls under Part A, with the Part A deductible and inpatient cost-sharing rules, and the stay can count toward the three-day requirement for SNF coverage.
• Outpatient: Some knee replacements — particularly partial replacements and procedures on healthier patients — are now done on an outpatient basis at hospitals or ambulatory surgery centers. Outpatient care is covered under Part B, with 20% coinsurance applying to covered services.

CMS removed total knee arthroplasty from the Medicare Inpatient-Only (IPO) list effective January 1, 2018, meaning hospitals and surgeons can perform the procedure on an outpatient basis when it is clinically appropriate. Being physically kept overnight for monitoring does not automatically make a stay “inpatient” — the classification depends on your surgeon’s order and the “two-midnight” expectation. This distinction can affect your cost-sharing, your SNF eligibility, and your recovery planning.

Because outpatient surgery may not satisfy the three-day inpatient requirement for Medicare-covered SNF care, it is worth asking directly. Confirm with your surgeon and hospital before the procedure how it will be billed, and get the answer in terms of your admission status, not just where you sleep that night.

Prior Authorization and Medical Necessity

For Original Medicare, knee replacement generally does not require prior authorization — your doctor documents medical necessity. However, most Medicare Advantage plans do require prior authorization for major surgeries, including knee replacement, so check your plan’s rules early.

To qualify as medically necessary, your condition typically must include:

• Significant knee pain and functional limitation from osteoarthritis, rheumatoid arthritis, or post-traumatic arthritis
• Failure of conservative treatments such as physical therapy, medications, injections, and activity modification
• Radiographic evidence of substantial joint damage
• Meaningful impact on daily activities and quality of life

Your orthopedic surgeon documents medical necessity based on your symptoms, imaging, and treatment history.

Recovery and Rehabilitation Coverage

Medicare covers rehabilitation services that are essential to recovery from knee replacement:

• Inpatient rehabilitation: If you qualify, Part A covers inpatient rehabilitation at a rehab facility or skilled nursing facility. You must meet specific criteria, including the ability to participate in intensive therapy (an inpatient rehab facility generally expects around three hours of therapy per day, several days per week).
• Outpatient physical therapy: Part B covers outpatient physical therapy to restore mobility, strength, and function. You pay 20% coinsurance after the Part B deductible.
• Home health services: If you are homebound after surgery and meet the criteria, Medicare covers home health services — including physical therapy, occupational therapy, and skilled nursing visits — at no cost to you for the covered home-health services themselves.

A typical recovery timeline includes:

• Hospital stay of one to three days, or same-day discharge for outpatient cases
• Use of a walker or crutches for two to four weeks
• Physical therapy for roughly six to twelve weeks
• Return to most daily activities within six to eight weeks
• Continued improvement toward full recovery over three to six months (sometimes up to a year)

Choosing a Surgeon and Facility

Your choice of surgeon and facility can affect both outcomes and cost:

• Medicare-participating providers: Choose a surgeon and facility that accept Medicare assignment to avoid excess charges.
• Hospital quality ratings: CMS publishes hospital quality data, including complication rates for joint replacement, through Medicare.gov’s Care Compare tool.
• Bundled-payment programs: Some hospitals participate in Medicare bundled-payment models for joint replacement, which are designed to reward higher quality and lower total cost.
• Surgeon volume: Research consistently links higher surgeon and hospital volume with better outcomes and fewer complications.

For more context on Medicare coverage policies and how they shape access to major procedures, visit our healthcare policy guide.

Frequently Asked Questions

Does Medicare cover both knees at the same time?

Medicare can cover bilateral (both knees) knee replacement in a single surgery when it is medically necessary. However, many orthopedic surgeons recommend staging the procedures weeks or months apart to allow for recovery and reduce surgical risk. Same-day bilateral surgery is generally reserved for carefully selected patients. Coverage applies the same way whether one or both knees are done.

How long is the hospital stay for knee replacement with Medicare?

Hospital stays have shortened considerably. Most inpatient total knee replacements involve a one- to three-day stay, and partial or outpatient total knee replacements may involve same-day discharge or a single overnight. Advances in surgical technique, pain management, and rehabilitation have driven the shift toward shorter stays.

Does Medicare cover robotic knee replacement?

Medicare covers the knee replacement procedure whether the surgeon uses traditional or robotic-assisted techniques; the surgeon’s fee and facility fee are covered the same way. Some hospitals incur higher costs for robotic systems, but under Medicare’s payment structure those costs are generally absorbed by the facility rather than billed separately to the patient.

Can Medicare deny knee replacement surgery?

Medicare rarely denies a well-documented, medically necessary knee replacement. Denials are more likely when documentation is insufficient, conservative treatments have not been adequately tried, or the procedure is classified incorrectly. Medicare Advantage plans may deny prior-authorization requests. In any case, you have the right to appeal a denial.

What if I need knee replacement but cannot afford the out-of-pocket costs?

Several options can help: Medigap plans cover most or all Original Medicare cost-sharing; some Medicare Advantage plans have lower out-of-pocket costs for surgery and an annual out-of-pocket maximum; Medicare Savings Programs help qualifying low-income beneficiaries with premiums and cost-sharing; and many hospitals offer financial assistance or payment plans. A benefits counselor or your State Health Insurance Assistance Program (SHIP) can walk you through the choices.

Practical Takeaway

Medicare does cover knee replacement, including the surgery, surgical fees, implant, rehabilitation, and follow-up care. Your out-of-pocket costs depend on whether you have Original Medicare (with or without Medigap) or a Medicare Advantage plan, and on whether the procedure is billed as inpatient or outpatient. Before scheduling surgery, confirm your inpatient-or-outpatient classification, understand the 2026 cost-sharing, check whether a Medicare Advantage plan requires prior authorization, and research your surgeon and facility using Medicare’s quality tools. Because these amounts change every year, verify the current figures at Medicare.gov. With a little planning, knee replacement on Medicare can be a manageable — and life-improving — experience.