Does Medicare Cover That? A Simple Rule for a More Complicated World
When folks first sit down with me, one of the things I tell them is that Medicare is accepted just about everywhere. And that’s true. Nearly every hospital in the country takes Medicare, and according to the Kaiser Family Foundation, 98% of physicians who bill Medicare are participating providers. Only about 1% of doctors nationwide have opted out of Medicare entirely. Those numbers are reassuring, and they should be.
But medicine has been changing, and where your care comes from matters more than it used to. More patients are stepping outside the traditional system. They’re seeing functional medicine doctors, concierge practices, direct-to-consumer screening companies, wellness clinics, and specialists who have chosen not to enroll in Medicare at all. That small slice of providers outside the system is exactly where the surprise bills come from. Some of these providers do good work. Some offer services that genuinely bring peace of mind. But when the bill arrives, a lot of people learn the hard way that Medicare won’t pay a penny of it.
So let me give you the rule I come back to again and again. If you remember nothing else, remember this:
Medicare pays when a service is medically necessary AND performed by a participating provider.
Both parts have to be true. Not one. Both.
Medically Necessary
This means the service has to be ordered to diagnose or treat a specific condition or symptom. A test your doctor orders because your bloodwork came back high? That can qualify. A broad, whole-body screening you decide to get on your own for peace of mind? Usually not, even if the very same test would have been covered under different circumstances.
The reason behind the service matters. Medicare is designed to pay for care that addresses a medical need, not general screening or wellness that a patient pursues on their own.
Performed by a Participating Provider
Here’s the part that trips people up the most. A provider has to actually be enrolled with Medicare for Medicare to pay them. If a clinic, lab or imaging company has opted out of Medicare entirely, there is no mechanism to file a claim, no matter how medically necessary the service was and no matter who ordered it.
I’ve had clients ask whether they can file the claim themselves in these situations. The honest answer is no. Medicare does allow a patient to submit their own claim in certain narrow cases, but only when a participating provider fails to file on their behalf. If the provider never participated in the first place, the claim gets denied regardless of who submits it.
And a quick note on Medicare Supplements, since a lot of my clients carry one: your supplement follows Medicare’s lead. It only pays after Medicare approves a claim. So if Medicare can’t pay because the provider doesn’t participate, your supplement can’t pick it up either. That door closes right along with the first one.
Why This Matters More Every Year
Functional medicine, cash-pay clinics, and direct-to-consumer testing have given patients more options than ever, and for a lot of people that’s a welcome thing. But those options come with a catch that isn’t always spelled out clearly at the point of sale: many of these providers sit completely outside the Medicare system.
That means the responsibility falls on you, the patient, to ask two questions before you commit:
1. Is this being ordered for a specific medical reason?
2. Does this provider participate in Medicare?
If the answer to either is no, plan on paying the full cost yourself, and decide going in whether it’s worth it to you.
A Word for My Medicare Advantage Clients
Everything above is written mainly for folks on Original Medicare with a supplement, which is a big share of the people I serve. If you’re on a Medicare Advantage plan, the same lesson holds, but the mechanics are a little different, and it’s worth understanding the twist.
With Advantage, the question isn’t just whether a provider takes Medicare. It’s whether that provider is in your plan’s network, and often whether your plan approved the service ahead of time through prior authorization. A provider operating outside the Medicare system is going to be out of network by definition, which usually means little or no coverage, and sometimes a bigger bill than you’d expect. So the same rule applies, just filtered through your plan’s network and its rules. When in doubt, call before you go.
The Bottom Line
I’m never going to tell someone not to pursue their health. If a test or a scan gives you peace of mind, that has real value, and sometimes it’s worth paying for out of pocket. But I do want my clients to understand the rules before the bill shows up, not after.
So keep the rule close: medically necessary, and by a participating provider. When both of those are true, Medicare usually works the way you’d expect. When one is missing, it’s a cash transaction, plain and simple. If you’re ever unsure whether something will be covered, that’s exactly the kind of question I’m here for. A five-minute phone call before your appointment can save you a good deal of money and frustration.
Frequently Asked Questions
Does Medicare cover a whole-body MRI or preventive scan? Generally no. Medicare covers imaging that is medically necessary and ordered to diagnose or treat a specific condition. Whole-body screening scans you arrange on your own, such as those from direct-to-consumer imaging companies, are typically not covered, even when the same scan might be covered if a doctor ordered it for a diagnosed problem.
Can I get reimbursed if I paid out of pocket for a test? Only if the service was performed by a Medicare-participating provider and is medically necessary. If the provider has opted out of Medicare entirely, there is no claim to file and no reimbursement available, regardless of who ordered the test. Filing the claim yourself does not change that outcome.
Will my Medicare Supplement pay if Medicare denies the claim? No. A Medicare Supplement pays only after Medicare approves a claim first. If Medicare will not pay because the provider does not participate, your supplement cannot pay either.
How do I know if a provider participates in Medicare? Ask the provider’s office directly whether they accept Medicare assignment, or check Medicare’s provider lookup. When in doubt, call before your appointment. A quick question up front can save you a large bill later.
What about Medicare Advantage plans? Medicare Advantage adds another layer: the provider must be in your plan’s network, and some services require prior authorization. A provider outside the Medicare system will be out of network, which usually means little or no coverage. Always confirm with your plan first.
Source: Kaiser Family Foundation, “How Many Physicians Have Opted Out of the Medicare Program?” (2025). Physician participation figures reflect the most recent CMS data.
Chris Schopmeyer is the owner of Schopmeyer Medicare, Health & Life, an independent brokerage serving the greater Jackson metro area. This article is for general educational purposes and is not a substitute for personalized coverage guidance. Have a question about your own plan? Reach out anytime.