James R. Nellen, MD
Anesthesiology Physician · Greenbrae, CA
James R. Nellen, MD is an anesthesiology physician with a practice address in Greenbrae, California, and NPI 1174086748, issued on Apr 10, 2019. Check the license (California A194708, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- James R. Nellen
- Credential
- MD
- Primary taxonomy
- Anesthesiology Physician 207L00000X
- License numbers
- A194708 CA
75283 WI
Self-reported in NPPES; status is on the state search - Practice location
- 250 Bon Air RD, Greenbrae, CA 94904
- Phone
- (415) 925-7100
- Enumerated
- Apr 10, 2019
- Record last updated
- Jun 10, 2024
- Medicare enrollment
- Enrolled (PECOS I20240622000006); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest anesthesiology physician records → All 7,571 in California → Look up another NPI →
Also registered at 250 Bon Air RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Lisa Abrahams, MFTMarriage & Family Therapist1184738445
- Jory Adam, PA-CSurgical Physician Assistant1922269521
- Samuel Adams, MDHospitalist Physician1497785034
- Barbara Addleman, RNRegistered Nurse1053551267
- Linda Alexander, RNPsychiatric/Mental Health Registered Nurse1205589405
- Maxwell AlikinneyCounselor1538668728
Verify James R. Nellen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A194708Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
The practice group's MIPS final score for 2023 (Medicare payment program): 77.4 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Anesthesiology Consultants OF MarinGreenbrae, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
James R. Nellen among 7,571 anesthesiology physician records in California
James R. Nellen, MD is one of 7,571 anesthesiology physician records with a practice address in California. 71% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2019, is newer than 89% of them.
- NPI issued2019 · 89% of these records are older, 8% newer
- In a Medicare fileYes · 71% of these records are
- In the CMS Doctors and Clinicians fileYes · 64% of these records are
- Graduated2019 · median 2006 among the 4,868 with a school on file
- Record last updated2024 · 63% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207L00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
46 anesthesiology physician records list a practice address in Greenbrae
They are 46 of the 727 NPPES records with a practice address in Greenbrae, and 7,571 anesthesiology physician records in California.
All 7,571 in California → Every provider in Greenbrae → Anesthesiology Physician nationwide →
The 8 anesthesiology physician records with the nearest ZIP codes
- T Benson, M.D.Greenbrae, CA 949041720016637
- James Brandes, M.D.Greenbrae, CA 949041417985334
- Keith Chamberlin, M.D.Greenbrae, CA 949041265544654
- Anthony Chiu, M.D.Greenbrae, CA 949041437269495
- Christophe Dinello, M.D.Greenbrae, CA 949041730270620
- Benjamin Hu, MDGreenbrae, CA 949041487691143
- Sonali Joshi, MDGreenbrae, CA 949041639281751
- Patrick Kwan, M.D.Greenbrae, CA 949041164468286
Common questions
What is James R. Nellen, MD's NPI number?
James R. Nellen, MD's National Provider Identifier (NPI) is 1174086748, issued on Apr 10, 2019. An NPI identifies a provider in billing; it is not a license.
Where is James R. Nellen, MD located?
The NPPES record lists a practice address at 250 Bon Air RD, Greenbrae, CA, 94904. Phone: (415) 925-7100. Providers update this record themselves, so call before visiting.
How can I verify James R. Nellen, MD's license?
NPPES lists California license number A194708, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
What is James R. Nellen, MD's MIPS final score?
The 2023 MIPS final score is 77.4 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.