If your doctor doesn’t accept Medicare, you’ll pay more out of pocket, but how much more depends on the type of non-acceptance. There are actually three distinct categories: participating providers (who fully accept Medicare), non-participating providers (who accept Medicare but not always its standard payment rates), and opt-out providers (who’ve left the Medicare program entirely). Each one changes your costs and rights in different ways.
Three Types of Medicare Acceptance
The phrase “doesn’t accept Medicare” can mean two very different things, and the distinction matters for your wallet.
A participating provider has agreed to accept Medicare’s approved amount as full payment for every service. Medicare pays them directly, and you’re only responsible for your standard deductible and coinsurance. This is the simplest, cheapest scenario for patients.
A non-participating provider is still enrolled in Medicare but hasn’t agreed to accept Medicare’s approved amount on every claim. They can decide claim by claim whether to accept Medicare’s rate. When they don’t accept it, they can charge you more than a participating provider would, but there’s a legal cap on how much more. Medicare also pays them 5% less than it pays participating providers for the same service.
An opt-out provider has formally left the Medicare program. Medicare won’t pay anything toward your care with this doctor. You’re entirely on your own financially. As of November 2024, only about 1.2% of non-pediatric physicians in the U.S. have opted out, so this situation is relatively uncommon, but it’s concentrated in certain specialties like psychiatry and some surgical fields.
What Non-Participating Providers Can Charge You
When a non-participating provider doesn’t accept assignment on your claim, they can bill you above Medicare’s approved amount. But federal law sets a ceiling called the “limiting charge,” which is 115% of the Medicare-approved fee schedule amount for non-participating providers. They cannot charge you a penny above that.
Here’s what that looks like in practice. Say Medicare’s approved amount for a service is $100 for a participating provider. A non-participating provider’s fee schedule is 5% lower, so their approved amount is $95. The most they can charge you is 115% of that $95, which comes to $109.25. Medicare will reimburse a portion of that $95, and you cover the rest, including the gap between Medicare’s payment and the limiting charge.
Non-participating providers are required to submit claims to Medicare on your behalf so you can get reimbursed for Medicare’s share. In some cases, though, you may need to pay the full amount upfront and wait for Medicare to send you the reimbursement. This is a key difference from participating providers, where Medicare pays the doctor directly and you never handle the larger payment.
What Happens With Opt-Out Providers
Seeing a doctor who has opted out of Medicare is the most expensive scenario. Before they can treat you, federal law requires both of you to sign a private contract. This isn’t just a formality. The contract must clearly state that you accept full responsibility for payment, that Medicare limits on charges don’t apply, that neither of you will submit a claim to Medicare, and that Medicare will not pay for any services under this arrangement.
There is no cap on what an opt-out provider can charge. The limiting charge rule doesn’t apply because they’ve left the Medicare system entirely. Your Medigap (Medicare supplement) plan will not cover these charges either, since Medigap only pays for costs related to Medicare-covered services. Some other supplemental plans may also decline to pay.
The contract cannot be signed during an emergency or urgent care situation. It must be provided to you before any services are rendered, and the doctor must keep the original signed copy for the duration of their two-year opt-out period. These opt-out periods renew every two years, and the contract must state the expected start and end dates.
How Medicare Advantage Plans Handle This
If you have a Medicare Advantage plan (like an HMO or PPO) rather than Original Medicare, the rules shift. Medicare Advantage plans build their own provider networks, so “not accepting Medicare” might mean the doctor doesn’t accept your specific plan rather than Medicare as a whole.
For out-of-network care, Medicare Advantage plans are generally required to reimburse non-contracted providers at least the Original Medicare rate. Non-contracted providers must accept that amount as payment in full, just as they would for someone on Original Medicare. Hospitals and similar facilities cannot balance bill Medicare Advantage enrollees at all.
Physicians who are non-participating with Original Medicare and don’t accept assignment can technically balance bill up to the same 115% limiting charge. But here’s an important protection: if that happens, your Medicare Advantage plan is legally required to cover the additional amount and shield you from charges above your plan’s normal cost-sharing. So in practice, Medicare Advantage enrollees have stronger protections against surprise charges from non-participating doctors than people on Original Medicare.
Private Fee-for-Service (PFFS) plans are an exception. These plans can set their own fee schedules and balance-billing rules that differ from Original Medicare, so the specifics depend on your plan’s terms.
Emergency Care Protections
In an emergency, you don’t need to worry about whether the doctor or hospital accepts Medicare. The Emergency Medical Treatment and Labor Act (EMTALA) requires all Medicare-participating hospitals with emergency departments to screen and stabilize anyone who comes in, regardless of insurance status or ability to pay. If the hospital can’t stabilize you, they must arrange an appropriate transfer.
Opt-out providers also cannot require you to sign a private contract during an emergency or urgent care situation. This means you retain your Medicare protections when time-sensitive care is needed, even if the treating physician has otherwise opted out of the program.
How to Check a Doctor’s Medicare Status
Before scheduling an appointment, you can look up any provider on Medicare’s Care Compare tool at Medicare.gov. The tool lets you search for Medicare-approved providers near you, compare care quality, and verify whether a doctor participates in Medicare, is non-participating, or has opted out.
When calling a new doctor’s office, ask specifically whether they “accept assignment” on Medicare claims. A receptionist who says “we accept Medicare” might mean the doctor is non-participating but will still bill Medicare. That’s a very different situation from a fully participating provider. The clearest question to ask is: “Do you accept Medicare assignment on all claims?”
If you’re seeing a non-participating provider, ask upfront whether they’ll accept assignment for your specific visit. Remember, non-participating providers can choose to accept Medicare’s approved amount on a case-by-case basis. They might accept assignment for a routine office visit but not for a more expensive procedure. Getting this clarified before your appointment helps you avoid unexpected bills.