Samuel Massion
NPI 1821793654 · Hospitalist Physician · San Francisco, CA
Enrolled with Medicare as Order and Referring Only - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Samuel Massion is a Hospitalist Physician provider in San Francisco, CA (NPI 1821793654).
Provider details
- NPI number
- 1821793654
- Entity type
- Individual
- Primary specialty
- Hospitalist PhysicianAllopathic & Osteopathic Physicians
- Sex
- Male
- Sole proprietor
- No
- License
- A201779 (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
3 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
- 2023-04-03
- Last updated
- 2026-05-20
- Certified
- 2026-05-20
Frequently asked questions
- What is Samuel Massion's NPI number?
- Samuel Massion's National Provider Identifier (NPI) is 1821793654, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Samuel Massion's specialty?
- Samuel Massion is listed in the NPPES registry with a primary specialty of Hospitalist Physician (Allopathic & Osteopathic Physicians).
- Where is Samuel Massion located?
- Samuel Massion's practice location on file with NPPES is 505 Parnassus Ave, San Francisco, CA 94143-2204.
- What is Samuel Massion's phone number?
- The practice phone number listed in the NPPES registry for Samuel Massion is (415) 476-1528.
- Does Samuel Massion accept Medicare?
- Samuel Massion is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Samuel Massion's NPI active?
- Yes — Samuel Massion's NPI (1821793654) is active in the NPPES registry as of the last update on 2026-05-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.