DR. DIANA HESS MD
NPI 1295296275
Internal Medicine in Castro Valley, CA
About Dr. Diana Hess Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. DIANA HESS MD (NPI 1295296275) is an individual internal medicine provider in Castro Valley, California, licensed in California (178427) and active in the NPI registry since March 2019. She is enrolled in Medicare PECOS, maintains 2 additional practice locations, and is a graduate of Univ Of Central Florida, College Of Medicine (2019).
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Locations 2
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. Diana Hess Md 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 Diana Hess reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Orinda, CA 94563
- Reassigned Medicare billing, California enrollment
- 4,479 clinicians in this Medicare group
Orange, CA 92868
- Reassigned Medicare billing, California enrollment
- 525 clinicians in this Medicare group
Orange, CA 92868
- Reassigned Medicare billing, California enrollment
- 75 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 3
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 94546 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 12
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
CASTRO VALLEY, CA 94546
CASTRO VALLEY, CA 94546
CASTRO VALLEY, CA 94546
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 Diana Hess's NPI number?
The NPI number for Diana Hess is 1295296275. It was assigned to this individual provider in the NPPES registry on March 30, 2019.
Where is Diana Hess located?
Diana Hess practices at 20101 Lake Chabot Rd Fl 3, Castro Valley, CA 94546. The listed phone number is (510) 886-3400.
What is Diana Hess's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Diana Hess enrolled in Medicare?
Yes. Diana Hess 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 Diana Hess's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Diana Hess reassigns Medicare benefits to 3 organizations: Sutter Bay Medical Foundation (Orinda, CA), Uc Regents (Orange, CA) and Regents Of The University Of California (Orange, 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 Diana Hess'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 Diana Hess was last updated on October 30, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 23 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.
# Dr. Diana Hess, MD · NPI 1295296275
Internal Medicine physician in Castro Valley, California. Individual provider, active in the CMS NPPES registry since March 30, 2019.
## Identity
- **NPI:** 1295296275 (Entity type: Individual)
- **Enumerated:** March 30, 2019
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** 178427 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 20101 LAKE CHABOT RD FL 3, Castro Valley, CA 94546-5305
- **Phone:** (510) 886-3400
## 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): Sutter Bay Medical Foundation (NPI 1366898538, Orinda, CA); Uc Regents (NPI 1003864174, Orange, CA); Regents Of The University Of California (NPI 1679521850, Orange, CA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Univ Of Central Florida, College Of Medicine, class of 2019
## Record status
- **NPPES last updated:** October 30, 2024
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Source: [NPI Profile](https://npiprofile.com/npi/1295296275) · Data from the CMS NPPES public registry.