ALLEN W. NAN MD
NPI 1750469326
Obstetrics & Gynecology in Antioch, CA
About Allen W. Nan Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
ALLEN W. NAN MD (NPI 1750469326) is an individual obstetrics & gynecology provider in Antioch, California, licensed in California (G73566) and active in the NPI registry since November 2006. He is enrolled in Medicare PECOS.
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 (PECOS)
Allen W. Nan Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Allen Nan reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Stockton, CA 95210
- Reassigned Medicare billing, California enrollment
- 20,078 clinicians in this Medicare group
Woodland, CA 95695
- Reassigned Medicare billing, Texas enrollment
- 89 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 94531 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.
ANTIOCH, CA 94531
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 Allen Nan's NPI number?
The NPI number for Allen Nan is 1750469326. It was assigned to this individual provider in the NPPES registry on November 1, 2006.
Where is Allen Nan located?
Allen Nan practices at 5601 Deer Valley Rd, Antioch, CA 94531. The listed phone number is (925) 813-6500.
What is Allen Nan's specialty?
The primary specialty registered for this NPI is Obstetrics & Gynecology with taxonomy code 207V00000X.
Is Allen Nan enrolled in Medicare?
Yes. Allen Nan is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Allen Nan's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Allen Nan reassigns Medicare benefits to 2 organizations: Permanente Medical Group Inc (Stockton, CA) and Northern Valley Indian Health Inc (Woodland, 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 Allen Nan'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 Allen Nan was last updated on December 13, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.
# Allen W. Nan, MD · NPI 1750469326
Obstetrics & Gynecology physician in Antioch, California. Individual provider, active in the CMS NPPES registry since November 1, 2006.
## Identity
- **NPI:** 1750469326 (Entity type: Individual)
- **Enumerated:** November 1, 2006
- **Primary specialty:** Obstetrics & Gynecology · taxonomy 207V00000X
- **State license:** G73566 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 5601 DEER VALLEY RD, Antioch, CA 94531-8577
- **Phone:** (925) 813-6500
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Permanente Medical Group Inc (NPI 1548343510, Stockton, CA); Northern Valley Indian Health Inc (NPI 1881960128, Woodland, CA) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** December 13, 2021
---
Source: [NPI Profile](https://npiprofile.com/npi/1750469326) · Data from the CMS NPPES public registry.