Access, decoded

Do all doctors take Medicare? Most do, and the exceptions come in three flavors

Short answer: the overwhelming majority of doctors treat Medicare patients, but "accepts Medicare" hides three distinct statuses with different bills. Participating doctors take Medicare’s rate as full payment. Non-participating doctors can charge up to 15% above it (the "excess charge"). Opted-out doctors, rare overall but concentrated in psychiatry and some specialties, work by private contract, and Medicare pays nothing. Learning to ask which one you’re booking is a two-minute skill that prevents genuine billing surprises.

By the Medicare Decoder team · Updated August 10, 2026 · 4-minute read · Figures are official 2026 amounts

Key takeaways

Participating providers (the vast majority) accept Medicare’s approved amount as full payment: you owe only your normal deductible and 20%.
Non-participating providers can bill up to 15% above the approved amount; Plan G covers excess charges, Plan N doesn’t, and eight states ban them.
Opted-out providers contract privately: Medicare pays nothing, and you sign an agreement to pay their full fee.
Advantage plans replace all of this with network logic: in-network, out-of-network, or not covered, per your plan’s rules.
Verify anyone in 60 seconds: Medicare.gov’s provider search shows status, or ask the office the one precise question below.

Jump to The three statuses The 15% explained The opt-outs On Advantage, different question How to check anyone FAQ

The three statuses, in one table

Status	What they can bill you	Your real cost
Participating ("accepts assignment")	Medicare’s approved amount, period	Deductible + 20% (which Medigap covers)
Non-participating	Up to 15% above the approved amount (the excess charge), banned in 8 states	Deductible + 20% + up to 15% excess (Plan G pays it; Plan N doesn’t)
Opted out	Whatever your private contract says	Everything; Medicare and Medigap pay $0 (true emergencies excepted)

Excess charges are banned in NY, CT, MA, MN, OH, PA, RI, and VT. Opt-out requires the doctor to file with Medicare and contract with each patient.

The 15%, demystified

Non-participating doctors haven’t left Medicare; they’ve declined the participation agreement, which lets them charge up to 15% over the (slightly reduced) approved amount on unassigned claims. In practice: an approved amount of $200 can become a $230 bill, with the extra $30 yours. Three deflations of the fear, though: most doctors participate fully, eight states ban excess charges outright, and the charges are capped by law at that 15%, so the exposure is bounded, not open-ended. This is precisely the risk that separates Plan G from Plan N: G pays excess charges, N doesn’t, and the arithmetic there covers when that difference matters.

The opt-outs: rare, but clustered where it hurts

Fully opted-out physicians file an affidavit with Medicare and treat patients only under private contracts: you sign, you pay their fee, Medicare and your Medigap plan pay nothing, and no claim is even submitted. The overall opt-out rate is low single digits, but it clusters: psychiatry leads by a wide margin (one reason the mental-health article spends a section on finding clinicians), with pockets in plastic surgery, dermatology, and concierge primary care. The contract you sign is the tell; nobody opts you out by surprise, but people do sign without reading.

On Medicare Advantage, the question changes

Advantage replaces the assignment framework with networks: the question isn’t "does this doctor take Medicare" but "is this doctor in this plan’s network this year." A doctor can adore Original Medicare and be out-of-network for your specific plan, and directories overstate reality often enough that the gold standard is calling the office: "Are you in-network for [exact plan name] for 2026, and taking new patients?" Networks also change annually, which is one of the five September numbers in the ANOC ritual.

The 60-second verification, either path

Original Medicare: search the provider at Medicare.gov (the care-comparison tools show whether a provider accepts assignment), or ask the office: "Do you accept Medicare assignment?" The word "assignment" signals you know the categories; the answer sorts them instantly.
Advantage: the exact-plan-name network question above, asked of the office, not the directory.
Any surprise bill: check the status first; a "Medicare denied this" letter from an opted-out or out-of-network encounter isn’t a coverage failure, it’s a category you can avoid next visit.

Questions people also ask

Do most doctors accept Medicare?

Yes; the large majority of physicians treat Medicare patients, and most of those are participating providers who accept Medicare’s approved amount as full payment. The exceptions are non-participating doctors (who can add up to 15%) and the small opted-out group who work by private contract.

What does it mean when a doctor accepts Medicare assignment?

That they accept Medicare’s approved amount as payment in full: you owe only your deductible and 20% coinsurance (which Medigap covers). Asking “do you accept assignment?” is the precise version of “do you take Medicare?”

What are Medicare excess charges?

The up-to-15% surcharge non-participating providers may add above Medicare’s approved amount. Medigap Plan G pays them; Plan N doesn’t; and New York, Connecticut, Massachusetts, Minnesota, Ohio, Pennsylvania, Rhode Island, and Vermont ban them entirely.

Can a doctor refuse Medicare completely?

Yes, by formally opting out and treating patients under private contracts: Medicare pays nothing and you pay the doctor’s full fee. Opt-out is rare overall but most common in psychiatry and some elective specialties. You’ll always sign a contract acknowledging it.

How do I check if my doctor takes my Medicare Advantage plan?

Ask the office directly whether they’re in-network for your exact plan name for the current year and accepting new patients; online directories lag reality. Networks change each January, so re-verify during fall enrollment if the doctor is a must-keep.

Sources for this article

Medicare.govMedicare.gov: provider search tools and assignment rules.
Medicare.govMedigap basics: which plans cover excess charges.
CMS.gov2026 premiums and deductibles: the cost-sharing baseline under assignment.

Figures checked against these sources in August 2026. We update within weeks when CMS publishes new amounts.

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