How to learn about a doctor accepts Medicare assignment
The fastest way is to call the doctor's office directly and ask: "Do you accept Medicare assignment?" A staff member can tell you in seconds whether they bill Medicare as their full payment for your visit, or whether they bill you for the difference between what Medicare pays and what they charge.
If you prefer to search online first, Medicare's official provider search tool — called the Provider Enrollment, Chain, and Ownership System (PECOS) — lets you look up whether a specific doctor or practice is enrolled to take Medicare. You can also call Medicare at 1-800-MEDICARE (1-800-633-4227) and give them the doctor's name and location; they will tell you whether that provider accepts Medicare assignment.
A third option is to ask your current doctor for a referral to a specialist and specifically request someone who accepts assignment. Many primary care doctors keep a list of specialists they work with regularly, and those relationships often mean assignment is already in place.
Key Takeaways
- Calling the doctor's office is the quickest way to confirm whether they accept Medicare assignment — ask directly and get a yes or no answer.
- Medicare's PECOS search tool and the 1-800-MEDICARE phone line both show whether a provider is enrolled to take Medicare, though enrollment does not always mean they accept assignment.
- When you call, also ask whether the practice is in-network with any Medicare Advantage plans you are considering, because that affects your out-of-pocket costs.
- If a doctor does not accept assignment, you can still see them, but you will owe the difference between Medicare's payment and their full charge unless you negotiate a lower rate upfront.
What Medicare assignment actually means
When a doctor accepts Medicare assignment, they agree to bill Medicare for the full allowed amount and accept what Medicare pays as payment in full. You pay only your share — the deductible, coinsitance, or copay — and nothing more. The doctor cannot bill you for the remainder.
When a doctor does not accept assignment, they can charge you for the difference between what Medicare pays and their full fee. This is called balance billing. For example, if a doctor's charge is $200, Medicare's allowed amount is $150, and Medicare pays $120, you might owe the doctor $80 (the $30 difference between the allowed amount and Medicare's payment, plus your $50 coinsurance). The doctor can also charge you the full $50 difference between their fee and the allowed amount.
There is one exception: doctors who do not accept assignment but have signed a Medicare participation agreement are limited in how much they can charge you above the Medicare-allowed amount. They can charge no more than 15 percent above what Medicare allows. This is called the limiting charge. Even so, you will owe more than you would with a doctor who accepts assignment.
Using Medicare's online provider search
Go to the Medicare.gov website and look for the "Care Provider Search" tool. You can search by name, location, or specialty. The results will show you whether the provider is enrolled with Medicare and whether they accept new patients.
The search does not always clearly state whether a provider accepts assignment. If the listing does not say, or if you are unsure what you are reading, call the provider directly or call Medicare at 1-800-MEDICARE. Do not assume enrollment means assignment — they are not the same thing.
You can also search for in-network providers if you are enrolled in a Medicare Advantage plan. Each plan has its own network, and seeing an in-network provider usually costs you less than seeing an out-of-network provider, even if both accept Medicare assignment.
Calling the doctor's office: what to ask
When you call, have the doctor's name and your Medicare number ready. Ask these three questions in order:
- "Do you accept Medicare assignment?" This is the core question. A yes means they bill Medicare as full payment. A no means they may balance-bill you.
- "Are you in-network with [name of your Medicare Advantage plan]?" If you have a Medicare Advantage plan, this matters as much as assignment. In-network providers have negotiated rates with your plan.
- "What is your current wait time for a new patient appointment?" This tells you whether you can actually see them soon, and gives you a chance to ask about telehealth visits if the wait is long.
Write down the name of the person who answered and the date you called. If you end up having a billing problem later, this record helps you prove what you were told.
What to do if a doctor does not accept assignment
You have three options. First, you can see the doctor anyway and pay the balance-billing amount. Before you do, ask the office in writing what the total charge will be, what Medicare will pay, and what you will owe. Get this in writing so there is no surprise bill later.
Second, you can ask the doctor whether they will negotiate a lower rate for you. Some doctors who do not accept assignment will agree to a reduced fee if you ask upfront and pay out of pocket. This is legal and happens more often than many people realize.
Third, you can find a different doctor who does accept assignment. This is often the simplest choice. Call your primary care doctor's office and ask for a referral to someone in your area who accepts Medicare assignment. If you need a specialist, your primary care doctor can usually point you toward someone who accepts assignment.
Assignment and Medicare Advantage plans
If you are enrolled in a Medicare Advantage plan, the concept of assignment works differently. Your plan has a network of doctors, and in-network providers have agreed to accept your plan's payment as full payment (with your copay or coinsurance). Out-of-network providers may balance-bill you.
When you search for a doctor, check whether they are in-network with your specific plan first. The Medicare.gov search tool lets you filter by plan. If a doctor is in-network, you do not need to ask about assignment — it is already built into your plan's contract with them.
If you are considering switching to a Medicare Advantage plan, make sure your current doctors are in-network before you enroll. Switching plans mid-year is difficult, so this choice matters.
What happens if you receive a balance bill
If a doctor balance-bills you and you believe they should not have, you can file a complaint with Medicare. Call 1-800-MEDICARE and explain what happened. Medicare can investigate whether the provider violated the assignment rules.
Keep all paperwork: the bill from the doctor, the Explanation of Benefits (EOB) from Medicare showing what they paid, and any written communication with the doctor's office. If the provider charged you more than the 15 percent limiting charge (if they are subject to it), Medicare will pursue the overage on your behalf.
You can also contact your state's insurance commissioner or your state's Medicare advocacy organization. Many states have patient advocates who help resolve billing disputes at no cost to you.
Frequently Asked Questions
If a doctor accepts Medicare, do they automatically accept assignment?
No. A doctor can be enrolled with Medicare and still choose not to accept assignment on every visit or for every patient. Some doctors accept assignment for some patients and not others. Always ask directly rather than assuming.
Can I ask a doctor to accept assignment if they normally do not?
Yes. Some doctors who do not accept assignment will make an exception if you ask upfront and agree to pay in full at the time of service. It never hurts to ask, especially if you do not have supplemental insurance to cover balance billing.
Does accepting Medicare assignment mean the doctor is in-network with my Medicare Advantage plan?
Not necessarily. A doctor can accept Medicare assignment but not be in-network with your specific plan. Check your plan's provider directory to be sure. If they are in-network, you are protected from balance billing. If they are out-of-network, you may owe more even if they accept assignment.
What is the difference between the limiting charge and balance billing?
Balance billing is any amount a doctor charges you above what Medicare allows. The limiting charge is a legal cap on balance billing — doctors subject to it can charge no more than 15 percent above the Medicare-allowed amount. Not all doctors are subject to the limiting charge, so some can balance-bill you more.
Can I use the Medicare.gov search tool to learn about a doctor accepts assignment?
The search tool shows whether a provider is enrolled with Medicare, but it does not always clearly state assignment status. Call the provider or Medicare directly to confirm. The online search is a good starting point, but a phone call gives you a definitive answer.