MARY WELTER
NPI 1902463979
Internal Medicine in San Francisco, CA
About Mary Welter NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARY WELTER (NPI 1902463979) is an individual internal medicine provider in San Francisco, California, licensed in California (A191802) and active in the NPI registry since May 2019. She is enrolled in Medicare PECOS, maintains a secondary practice location in San Francisco, and is a graduate of University Of California, Davis School Of Medicine (2021).
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Mary Welter is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
5Medicare enrollment records show Mary Welter reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
San Francisco, CA 94143
- Reassigned Medicare billing, California enrollment
- 2,112 clinicians in this Medicare group
San Francisco, CA 94143
- Reassigned Medicare billing, California enrollment
- 5,645 clinicians in this Medicare group
San Francisco, CA 94122
- Reassigned Medicare billing, California enrollment
- 5,544 clinicians in this Medicare group
San Francisco, CA 94116
- Reassigned Medicare billing, California enrollment
- 1,573 clinicians in this Medicare group
San Francisco, CA 94110
- Reassigned Medicare billing, California enrollment
- 637 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 94143 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
SAN FRANCISCO, CA 94143
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Mary Welter's NPI number?
The NPI number for Mary Welter is 1902463979. It was assigned to this individual provider in the NPPES registry on May 23, 2019.
Where is Mary Welter located?
Mary Welter practices at 521 Parnassus Ave, San Francisco, CA 94143. The listed phone number is (415) 885-3723.
What is Mary Welter's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Mary Welter enrolled in Medicare?
Yes. Mary Welter is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Mary Welter's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mary Welter reassigns Medicare benefits to 5 organizations: Regents Of The University Of California (San Francisco, CA), University Of California San Francisco (San Francisco, CA), Ucsf Medical Group Business Services (San Francisco, CA), City & County Of San Francisco (San Francisco, CA) and University Of California Sfgh Medical Group (San Francisco, CA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Mary Welter's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Mary Welter was last updated on October 11, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Mary Welter · NPI 1902463979
Internal Medicine physician in San Francisco, California. Individual provider, active in the CMS NPPES registry since May 23, 2019.
## Identity
- **NPI:** 1902463979 (Entity type: Individual)
- **Enumerated:** May 23, 2019
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** A191802 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 521 PARNASSUS AVE, San Francisco, CA 94143-2206
- **Phone:** (415) 885-3723
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 5 organizations under Medicare reassignment (form CMS-855R): Regents Of The University Of California (NPI 1376613943, San Francisco, CA); University Of California San Francisco (NPI 1346329380, San Francisco, CA); Ucsf Medical Group Business Services (NPI 1477624104, San Francisco, CA); City & County Of San Francisco (NPI 1528083300, San Francisco, CA); University Of California Sfgh Medical Group (NPI 1356696215, San Francisco, CA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of California, Davis School Of Medicine, class of 2021
## Record status
- **NPPES last updated:** October 11, 2024
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Source: [NPI Profile](https://npiprofile.com/npi/1902463979) · Data from the CMS NPPES public registry.