How to choose a doctor
What the Medicare data on our doctor pages means (NPI, specialty, hospitals, Medicare assignment), how to check a doctor, what to ask, who pays and where to complain.
Who this guide is for
For anyone looking for a primary care provider (a regular place for checkups and common health problems) or a specialist, and for families helping them. A primary care provider can be a family medicine doctor, an internist, a pediatrician, a geriatrician or an OB-GYN. In some practices a nurse practitioner or physician assistant is your primary care provider.
What the official data on our pages means
- NPI number
- The National Provider Identifier: a permanent 10-digit federal number for each clinician. You can look it up in the free official NPI Registry run by CMS. Each doctor page links to it.
- Specialty
- The primary specialty, and any others, that Medicare lists for the clinician. It is what the clinician reported to Medicare. It does not say whether the doctor is board certified: ask.
- Hospitals
- The hospitals that Medicare’s data links to the clinician, where they work or have privileges. If you may need a hospital stay, these are usually the hospitals where your doctor can treat you. See how to choose a hospital.
- Medical school and graduation year
- As listed in Medicare’s national clinician file. The graduation year is not the same as years in practice.
- Accepts Medicare assignment
- The clinician agrees to take the Medicare-approved amount as full payment for covered services. With Original Medicare you then pay only your deductible and coinsurance, and the office sends the claim to Medicare for you. Ask the office to confirm before your visit.
- Telehealth
- Medicare’s data says the clinician offers visits by video or phone. Ask which visits can be done that way.
Questions to ask when you call or visit
- Is the doctor taking new patients? Do you accept my insurance or Medicare plan, and do you accept Medicare assignment?
- Is the doctor board certified in their specialty?
- Which hospitals does the doctor use if I need a hospital stay?
- How soon can I get an appointment? How do I reach the office with a question, and who do I call after hours?
- Do staff or interpreters speak my language?
- Write down your questions and bring a list of all your medicines to the first visit.
Warning signs
- The doctor’s licence is not active, or the state medical board lists public actions against it. You can look up a doctor’s licence on your state medical board’s website.
- The doctor has opted out of Medicare. Medicare will not pay for their services (except in emergencies), and you pay under a private contract.
- The office will not tell you whether it takes your insurance or what a visit will cost.
Costs and who pays
Original Medicare (Part B) helps pay for doctor visits and outpatient care, usually 80% of the Medicare-approved amount after the yearly deductible, so you pay 20% coinsurance. Most preventive services cost you nothing when the doctor accepts assignment.
Doctors who do not accept assignment can charge you more than the Medicare-approved amount, in many cases up to 15% more (the “limiting charge”). Doctors who opt out of Medicare are not paid by Medicare at all, except in emergencies.
If you have a Medicare Advantage plan or other insurance, call the plan first: it may need to approve the care in advance and may only pay for providers in its network.
Medicaid is run by each state with federal rules, for people with limited income and savings. Rules, covered services and waiting lists differ by state: ask your state Medicaid agency.
In general terms only. Deductibles, coinsurance and other amounts change every year, and Medicaid rules differ by state: check Medicare.gov, call 1-800-MEDICARE or your state Medicaid agency, and ask your plan.
How to complain or get help
- Talk to the doctor or the office manager first.
- State medical board: licenses doctors and takes complaints about a doctor’s care or conduct. Nurse practitioners and other clinicians are licensed by their own state boards (for example the board of nursing).
- People with Medicare: the BFCC-QIO for your state reviews complaints about the quality of care you got for a Medicare-covered service.
- Medicare: 1-800-MEDICARE (1-800-633-4227), TTY 1-877-486-2048, free, with help in Spanish and other languages.
Find care on US Patient Guide
Common questions
How can I check a doctor’s NPI?
Search the doctor’s name or number in the free NPI Registry run by CMS. It shows the clinician’s specialty and practice address as the clinician reported them. Every doctor page on our site links to the doctor’s NPI Registry record.
What does “accepts Medicare assignment” mean?
The doctor agrees to take the Medicare-approved amount as full payment for covered services. You pay only the deductible and coinsurance, and the doctor sends the claim to Medicare. A doctor who does not accept assignment can charge more, in many cases up to 15% above the approved amount.
Can a nurse practitioner be my primary care provider?
Yes, in many practices. Nurse practitioners and physician assistants are trained and licensed differently from doctors, and in some practices they are the primary care provider.
Sources
- Choosing a primary care provider (MedlinePlus, National Library of Medicine)
- Does your provider accept Medicare as full payment? (Medicare.gov)
- NPI Registry (CMS)
- Medicare Care Compare (Medicare.gov)
- Questions to ask your doctor (Agency for Healthcare Research and Quality)
- Quality Improvement Organizations (CMS QIO Program)
- Choosing a primary care provider, in Spanish (MedlinePlus)
- Medicare.gov in Spanish
Written in plain language by US Patient Guide from the official sources above, November 11, 2026. The facts on each provider page come from the official data shown on that page, with its date. Not medical advice.