“Non-par” is short for “non-participating,” a term used in Medicare to describe a doctor or healthcare provider who accepts Medicare but has not signed an agreement to take Medicare’s approved payment as the full price for every service. This matters to you because seeing a non-par provider can cost more out of pocket than seeing a participating one, sometimes significantly more.
How Non-Par Providers Differ From Participating Ones
When a provider “participates” in Medicare, they agree to accept assignment on all claims. That means they treat Medicare’s approved amount as the final word on what a service costs. They bill Medicare directly, get paid directly, and can only collect your deductible and coinsurance from you.
A non-participating provider still works with Medicare, but they haven’t made that blanket agreement. They can decide on a case-by-case basis whether to accept assignment for a particular visit or service. When they don’t accept assignment, they’re allowed to charge you more than what Medicare approves, up to a legal cap called the limiting charge. They also receive a lower reimbursement rate from Medicare: their approved amount is 5% less than what a participating provider would get for the same service.
This is an important distinction from providers who have opted out of Medicare entirely. Opt-out providers don’t bill Medicare at all, can charge whatever they want, and require you to sign a private contract acknowledging you’ll pay the full cost yourself. Medicare won’t reimburse you for care from an opt-out provider except in emergencies. Non-par providers, by contrast, still operate within the Medicare system.
What You’ll Actually Pay
The extra cost of seeing a non-par provider comes down to something called the limiting charge. Non-par providers can bill you up to 115% of their Medicare-approved amount (which, remember, is already 5% lower than the participating rate). That 15% above their approved amount is known as the “excess charge,” and it comes out of your pocket.
Here’s how that adds up. With a participating provider, you’re typically responsible for 20% coinsurance on the Medicare-approved amount. With a non-par provider who charges the full limiting charge, you could owe up to 35% of the approved amount: 20% coinsurance plus the 15% excess. On a $200 service, that’s the difference between paying $40 and paying roughly $70.
Some states cap this even further. New York, for example, limits the excess charge to 5% instead of 15% for most services. It’s worth checking whether your state has similar protections.
How Billing Works in Practice
When a non-par provider doesn’t accept assignment for your visit, you may need to pay the full cost upfront. The provider is still required to submit a claim to Medicare on your behalf. After Medicare processes it, you’ll receive a Medicare Summary Notice and a reimbursement check for 80% of the Medicare-approved amount. You’re responsible for the rest, including the excess charge.
When a non-par provider does accept assignment for a specific service, the billing looks the same as it would with a participating provider. Medicare pays the provider directly, and you owe only your deductible and coinsurance. The key difference is that acceptance isn’t guaranteed for every visit.
For non-emergency surgeries expected to cost $500 or more, non-par providers who aren’t accepting assignment must give you a written notice beforehand. That notice has to spell out the charge for the surgery, what Medicare is likely to approve and pay, and what your out-of-pocket expense will be. This gives you a chance to weigh your options before committing.
Can Medigap Help Cover the Extra Cost?
If you have a Medigap (Medicare Supplement) policy, some plans cover Part B excess charges, which is the amount between the Medicare-approved price and the limiting charge. Not all Medigap plans include this benefit, so check the specifics of your plan. If you frequently see non-par providers, a plan that covers excess charges can save you real money over time.
How to Know If Your Provider Is Non-Par
You can ask any provider’s office directly whether they participate in Medicare or are non-participating. Medicare’s online provider directory also indicates participation status. The practical question to ask is: “Do you accept assignment?” If the answer is “sometimes” or “it depends,” you’re dealing with a non-par provider, and you should ask upfront whether they’ll accept it for your specific visit.
If you’re scheduling something expensive, like surgery or imaging, asking this question before the appointment lets you compare costs or find a participating provider who will accept Medicare’s approved amount as full payment. For routine office visits, the excess charge may be small enough that it doesn’t change your decision, but it’s still useful to know what to expect on the bill.