Grant Colfax, MD
NPI 1871610246 · Internal Medicine Physician · San Francisco, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Grant Colfax, MD is a Internal Medicine Physician provider in San Francisco, CA (NPI 1871610246).
Provider details
- NPI number
- 1871610246
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G81197 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-23
- Last updated
- 2010-07-20
Frequently asked questions
- What is Grant Colfax's NPI number?
- Grant Colfax's National Provider Identifier (NPI) is 1871610246, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Grant Colfax's specialty?
- Grant Colfax is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Grant Colfax located?
- Grant Colfax's practice location on file with NPPES is 995 Potrero Ave Bldg 90, San Francisco, CA 94110-2859.
- What is Grant Colfax's phone number?
- The practice phone number listed in the NPPES registry for Grant Colfax is (415) 206-8317.
- Does Grant Colfax accept Medicare?
- Grant Colfax is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Grant Colfax's NPI active?
- Yes — Grant Colfax's NPI (1871610246) is active in the NPPES registry as of the last update on 2010-07-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.