MICHAEL CHAFFIN N.P.
NPI 1558640235
Nurse Practitioner in Mountain View, CA
About Michael Chaffin N.p. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MICHAEL CHAFFIN N.P. (NPI 1558640235) is an individual nurse practitioner in Mountain View, California, licensed in California (20962) and active in the NPI registry since August 2011. He is enrolled in Medicare PECOS, maintains a secondary practice location in Concord, and is a graduate of Other (2011).
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
Michael Chaffin N.p. 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
4Medicare enrollment records show Michael Chaffin reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Santa Clara, CA 95051
- Reassigned Medicare billing, California enrollment
- 20,078 clinicians in this Medicare group
Palo Alto, CA 94301
- Reassigned Medicare billing, California enrollment
- 4,479 clinicians in this Medicare group
Castro Valley, CA 94546
- Reassigned Medicare billing, California enrollment
- 132 clinicians in this Medicare group
Fairfield, CA 94534
- Reassigned Medicare billing, California enrollment
- Also billed through NPI 1467825844 (California), NPI 1972877264 (California), NPI 1457593980 (California)
- 3,056 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 94040 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.
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.
MOUNTAIN VIEW, CA 94040
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 Michael Chaffin's NPI number?
The NPI number for Michael Chaffin is 1558640235. It was assigned to this individual provider in the NPPES registry on August 11, 2011.
Where is Michael Chaffin located?
Michael Chaffin practices at 701 E El Camino Real, Mountain View, CA 94040. The listed phone number is (650) 934-7150.
What is Michael Chaffin's specialty?
The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.
Is Michael Chaffin enrolled in Medicare?
Yes. Michael Chaffin 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 Michael Chaffin's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Michael Chaffin reassigns Medicare benefits to 4 organizations: Permanente Medical Group Inc (Santa Clara, CA), Sutter Bay Medical Foundation (Palo Alto, CA), Sutter Bay Hospitals (Castro Valley, CA) and Sutter Valley Medical Foundation (Fairfield, 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 Michael Chaffin'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 Michael Chaffin was last updated on April 3, 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.
# Michael Chaffin, N.P. · NPI 1558640235
Nurse Practitioner physician in Mountain View, California. Individual provider, active in the CMS NPPES registry since August 11, 2011.
## Identity
- **NPI:** 1558640235 (Entity type: Individual)
- **Enumerated:** August 11, 2011
- **Primary specialty:** Nurse Practitioner · taxonomy 363L00000X
- **State license:** 20962 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 701 E EL CAMINO REAL, Mountain View, CA 94040-2833
- **Phone:** (650) 934-7150
## 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:** 4 organizations under Medicare reassignment (form CMS-855R): Permanente Medical Group Inc (NPI 1073606299, Santa Clara, CA); Sutter Bay Medical Foundation (NPI 1013950807, Palo Alto, CA); Sutter Bay Hospitals (NPI 1063812907, Castro Valley, CA); Sutter Valley Medical Foundation (NPI 1184859894, Fairfield, CA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2011
## Record status
- **NPPES last updated:** April 3, 2024
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Source: [NPI Profile](https://npiprofile.com/npi/1558640235) · Data from the CMS NPPES public registry.