DR. CYNTHIA LYNN FENTON M.D.
NPI 1063720431
Internal Medicine in Mill Valley, CA
About Dr. Cynthia Lynn Fenton M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. CYNTHIA LYNN FENTON M.D. (NPI 1063720431) is an individual internal medicine provider in Mill Valley, California, licensed in California (G071207) and active in the NPI registry since September 2010. She is enrolled in Medicare PECOS and is a graduate of University Of California, San Diego School Of Medicine (1989).
NPPES Registry Identity
Specialties & Licenses
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
Dr. Cynthia Lynn Fenton M.d. 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
3Medicare enrollment records show Cynthia Fenton reassigns Medicare billing to 3 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 94122
- Reassigned Medicare billing, California enrollment
- 5,544 clinicians in this Medicare group
San Francisco, CA 94143
- Reassigned Medicare billing, California enrollment
- 5,645 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 4
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 94941 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
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 Cynthia Fenton's NPI number?
The NPI number for Cynthia Fenton is 1063720431. It was assigned to this individual provider in the NPPES registry on September 20, 2010.
Where is Cynthia Fenton located?
Cynthia Fenton practices at 315 Carrera Dr, Mill Valley, CA 94941. The listed phone number is (415) 300-6226.
What is Cynthia Fenton's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Cynthia Fenton enrolled in Medicare?
Yes. Cynthia Fenton 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 Cynthia Fenton's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Cynthia Fenton reassigns Medicare benefits to 3 organizations: Regents Of The University Of California (San Francisco, CA), Ucsf Medical Group Business Services (San Francisco, CA) and University Of California San Francisco (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 Cynthia Fenton'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 Cynthia Fenton was last updated on September 20, 2010. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.
# Dr. Cynthia Lynn Fenton, M.D. · NPI 1063720431
Internal Medicine physician in Mill Valley, California. Individual provider, active in the CMS NPPES registry since September 20, 2010.
## Identity
- **NPI:** 1063720431 (Entity type: Individual)
- **Enumerated:** September 20, 2010
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** G071207 (California)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 315 CARRERA DR, Mill Valley, CA 94941-3995
- **Phone:** (415) 300-6226
## 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:** 3 organizations under Medicare reassignment (form CMS-855R): Regents Of The University Of California (NPI 1235322348, San Francisco, CA); Ucsf Medical Group Business Services (NPI 1477624104, San Francisco, CA); University Of California San Francisco (NPI 1164512851, San Francisco, CA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of California, San Diego School Of Medicine, class of 1989
## Record status
- **NPPES last updated:** September 20, 2010
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Source: [NPI Profile](https://npiprofile.com/npi/1063720431) · Data from the CMS NPPES public registry.