Grant Colfax, MD
Internal Medicine Physician · San Francisco, CA
Grant Colfax, MD is an internal medicine physician with a practice address in San Francisco, California, and NPI 1871610246, issued on Mar 23, 2007. Check the license on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Grant Colfax
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- Practice location
- 995 Potrero Ave Bldg 90, San Francisco, CA 94110
- Phone
- (415) 206-8317
- Enumerated
- Mar 23, 2007
- Entity
- Type 1 · individual
Also registered at 995 Potrero Ave Bldg 90
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gilbert Arellano, RNAddiction (Substance Use Disorder) Registered Nurse1801745989
- Tamara Bogar TuckerAddiction (Substance Use Disorder) Registered Nurse1477253003
- Kristine Gu, MDEndocrinology, Diabetes & Metabolism Physician1033614888
- Wondelyn Nettles-Tutwiler, DRUG AND ALCOHOLAddiction (Substance Use Disorder) Counselor1740879709
- Courtney PopeCase Manager/Care Coordinator1417197534
- Emma WeinbergerMental Health Counselor1134660475
Verify Grant Colfax in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of CaliforniaCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
100% fewer Medicare Part D claims than the average internal medicine physician in 2024
12 Medicare Part D claims, against an average of 2,785 among the 127,794 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.
1,593 internal medicine physician records list a San Francisco practice address
They are 1,593 of the 38,143 NPPES records with a San Francisco practice address, and 20,403 internal medicine physician records in California.
All 1,593 in San Francisco → All 20,403 in California → Every provider in San Francisco →
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- Marce AbareScotts Valley, CA1457744708
- Samuel Abarte, M.D.Chula Vista, CA1578535498
- Alexander Abary, MDLong Beach, CA1104995919
- Luba Abascal, MDSan Francisco, CA1023180874
- Michael Abate, MDSacramento, CA1548248131
- Wali Abawi, D.O.Joshua Tree, CA1104362268
Common questions
What is Grant Colfax, MD's NPI number?
Grant Colfax, MD's National Provider Identifier (NPI) is 1871610246, issued on Mar 23, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Grant Colfax, MD located?
The NPPES record lists a practice address at 995 Potrero Ave Bldg 90, San Francisco, CA, 94110. Phone: (415) 206-8317. Providers update this record themselves, so call before visiting.
How can I verify Grant Colfax, MD's license?
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 Grant Colfax, MD prescribe under Medicare Part D?
In 2024, Grant Colfax, MD had 12 Medicare Part D claims; the average among internal medicine physician prescribers was 2,785. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 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.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.