Mary Welter
NPI 1902463979 · Internal Medicine Physician · San Francisco, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mary Welter is a Internal Medicine Physician provider in San Francisco, CA (NPI 1902463979).
Provider details
- NPI number
- 1902463979
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Sex
- Female
- Sole proprietor
- No
- License
- A191802 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
7 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
68 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 68 | $132 |
Typical Medicare-allowed amounts for these services range $132–$132 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Additional practice locations (1)
- 1001 Potrero Ave Bldg 25San Francisco, CA 94110-3518Phone: (628) 206-8000Fax: (628) 206-8965
Registry dates
- Enumerated
- 2019-05-23
- Last updated
- 2024-10-11
- Certified
- 2024-10-11
Frequently asked questions
- What is Mary Welter's NPI number?
- Mary Welter's National Provider Identifier (NPI) is 1902463979, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mary Welter's specialty?
- Mary Welter is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mary Welter located?
- Mary Welter's practice location on file with NPPES is 521 Parnassus Ave, San Francisco, CA 94143-2206.
- What is Mary Welter's phone number?
- The practice phone number listed in the NPPES registry for Mary Welter is (415) 885-3723.
- Does Mary Welter accept Medicare?
- Mary Welter is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mary Welter's NPI active?
- Yes — Mary Welter's NPI (1902463979) is active in the NPPES registry as of the last update on 2024-10-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.