James W. Ostroff, MD
Gastroenterology Physician · San Francisco, CA
James W. Ostroff, MD is a gastroenterology physician with a practice address in San Francisco, California, and NPI 1477505881, issued on May 16, 2006. Check the license (California G41522, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- James W. Ostroff
- Credential
- MD
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- G41522 CA
Self-reported in NPPES; status is on the state search - Practice location
- 350 Parnassus Ave, San Francisco, CA 94117
- Phone
- (415) 502-2112
- Enumerated
- May 16, 2006
- Record last updated
- Oct 25, 2009 (not updated in 17 years: call before relying on the address or phone)
- Fax
- (415) 514-3400
- Medicaid ID
- 00G415220 CA
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
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Verify James W. Ostroff in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G41522Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Industry payments in 2024: $101.00
2 payments; by number, the most common kind was food and beverage; the largest payer was Mauna Kea Technologies, Inc. The 13,350 providers of this specialty with any payment received $5,015.95 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
James W. Ostroff among 2,140 gastroenterology physician records in California
James W. Ostroff, MD is one of 2,140 gastroenterology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 7% of them.
- NPI issued2006 · 7% of these records are older, 48% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileNo · 72% of these records are
- Record last updated2009 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in San Francisco → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Brock Macdonald, M.D.San Francisco, CA 941171689901506
- Harvey Watts, M.D.San Francisco, CA 941171184640872
- Wing Kam, M.D., PH.D.San Francisco, CA 941181003964826
- Dean Rider, MDSan Francisco, CA 941181487759296
- Zealous Wiley, MDOakland, CA 941161740232610
- Waseem Ahmad, M.D.San Francisco, CA 941151649633991
- Timothy Chen, M.D.San Francisco, CA 941151699017707
- Charlotte Ching, MDSan Francisco, CA 941151407475312
Common questions
What is James W. Ostroff, MD's NPI number?
James W. Ostroff, MD's National Provider Identifier (NPI) is 1477505881, issued on May 16, 2006. An NPI identifies a provider in billing; it is not a license.
Where is James W. Ostroff, MD located?
The NPPES record lists a practice address at 350 Parnassus Ave, San Francisco, CA, 94117. Phone: (415) 502-2112. Providers update this record themselves, so call before visiting.
How can I verify James W. Ostroff, MD's license?
NPPES lists California license number G41522, 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.
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.