TAMSIN BARKER MSN, NNP-BC
NPI 1538049721
Nurse Practitioner - Neonatal, Critical Care in San Francisco, CA
About Tamsin Barker Msn, Nnp-bc NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
TAMSIN BARKER MSN, NNP-BC (NPI 1538049721) is an individual neonatal, critical care provider in San Francisco, California, licensed in California (95036643) and active in the NPI registry since September 2025. She is enrolled in Medicare PECOS and is a graduate of Other (2024).
NPPES Registry Identity
Specialties & Licenses
Other Names 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Tamsin Barker Msn, Nnp-bc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
4Medicare enrollment records show Tamsin Barker reassigns Medicare billing to 4 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
- 761 clinicians in this Medicare group
San Francisco, CA 94143
- Reassigned Medicare billing, California enrollment
- 1,159 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
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
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.
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 Tamsin Barker's NPI number?
The NPI number for Tamsin Barker is 1538049721. It was assigned to this individual provider in the NPPES registry on September 8, 2025. The provider is also known as Tamsin Summers.
Where is Tamsin Barker located?
Tamsin Barker practices at 1975 4th St, San Francisco, CA 94143. The listed phone number is (415) 290-7760.
What is Tamsin Barker's specialty?
The primary specialty registered for this NPI is Nurse Practitioner, specializing in Neonatal, Critical Care, with taxonomy code 363LN0005X.
Is Tamsin Barker enrolled in Medicare?
Yes. Tamsin Barker is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Tamsin Barker's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Tamsin Barker reassigns Medicare benefits to 4 organizations: Ucsf Dept Of Surgery (San Francisco, CA), Ucsf Pediatrics Associates (San Francisco, CA), University Of California San Francisco (San Francisco, CA) and Ucsf Medical Group Business Services (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 Tamsin Barker'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 Tamsin Barker was last updated on September 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 months 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.
# Tamsin Barker, MSN, NNP-BC · NPI 1538049721
Neonatal, Critical Care physician in San Francisco, California. Individual provider, active in the CMS NPPES registry since September 8, 2025.
## Identity
- **NPI:** 1538049721 (Entity type: Individual)
- **Enumerated:** September 8, 2025
- **Primary specialty:** Nurse Practitioner - Neonatal, Critical Care · taxonomy 363LN0005X
- **State license:** 95036643 (California)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 1975 4TH ST, San Francisco, CA 94143-2351
- **Phone:** (415) 290-7760
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 4 organizations under Medicare reassignment (form CMS-855R): Ucsf Dept Of Surgery (NPI 1477627537, San Francisco, CA); Ucsf Pediatrics Associates (NPI 1376614016, San Francisco, CA); University Of California San Francisco (NPI 1346329380, San Francisco, CA); Ucsf Medical Group Business Services (NPI 1477624104, San Francisco, CA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2024
## Record status
- **NPPES last updated:** September 9, 2025
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Source: [NPI Profile](https://npiprofile.com/npi/1538049721) · Data from the CMS NPPES public registry.