James Gregory Tappan, M.D.
Obstetrics & Gynecology Physician · San Mateo, CA
James Gregory Tappan, M.D. is an obstetrics & gynecology physician with a practice address in San Mateo, California, and NPI 1801880398, issued on Sep 12, 2005. Check the license (California A23884, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- James Gregory Tappan
- Credential
- M.D.
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- A23884 CA
Self-reported in NPPES; status is on the state search - Practice location
- 20 W 3RD Ave, San Mateo, CA 94402
- Phone
- (650) 347-5065
- Enumerated
- Sep 12, 2005
- Record last updated
- Mar 7, 2023
- Fax
- (650) 348-3425
- Medicaid ID
- GR0063440 CA
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Verify James Gregory Tappan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A23884Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
50% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
82 Medicare Part D claims, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
James Gregory Tappan among 5,088 obstetrics & gynecology physician records in California
James Gregory Tappan, M.D. is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 95% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileNo · 53% of these records are
- Record last updated2023 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Obstetrics & Gynecology Physician providers in California
There are 5,088 obstetrics & gynecology physician records in California.
All 5,088 in California → Every provider in San Mateo → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Isabell Beddow, MDSan Mateo, CA 944021942374269
- Zelda De La Cruz, MDSan Mateo, CA 944021376543256
- Rubina Khilnani, MDSan Mateo, CA 944021750381638
- Charles Winkelstein, M.D.San Mateo, CA 944021477740769
- Shelley Adams, MDSan Mateo, CA 944011891801932
- John Anderson, MDSan Mateo, CA 944031013082429
- Maryam Arjomand, M.D.San Mateo, CA 944011689763781
- Sandra Beretta, MDSan Mateo, CA 944011568573889
Common questions
What is James Gregory Tappan, M.D.'s NPI number?
James Gregory Tappan, M.D.'s National Provider Identifier (NPI) is 1801880398, issued on Sep 12, 2005. An NPI identifies a provider in billing; it is not a license.
Where is James Gregory Tappan, M.D. located?
The NPPES record lists a practice address at 20 W 3RD Ave, San Mateo, CA, 94402. Phone: (650) 347-5065. Providers update this record themselves, so call before visiting.
How can I verify James Gregory Tappan, M.D.'s license?
NPPES lists California license number A23884, 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.
How much does James Gregory Tappan, M.D. prescribe under Medicare Part D?
In 2024, James Gregory Tappan, M.D. had 82 Medicare Part D claims; the average among obstetrics & gynecology physician prescribers was 165. Part D covers Medicare prescriptions only.
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.