ALAN R. WILLIAMS MD
NPI 1407934128
Neurological Surgery in Sacramento, CA
About Alan R. Williams Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
ALAN R. WILLIAMS MD (NPI 1407934128) is an individual neurological surgery provider in Sacramento, California, licensed in California (G67524) and active in the NPI registry since November 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Alan R. Williams Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Alan Williams reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Stockton, CA 95210
- Reassigned Medicare billing, California enrollment
- 20,078 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 95825 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.
SACRAMENTO, CA 95825
SACRAMENTO, CA 95825
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 Alan Williams's NPI number?
The NPI number for Alan Williams is 1407934128. It was assigned to this individual provider in the NPPES registry on November 1, 2006.
Where is Alan Williams located?
Alan Williams practices at 2025 Morse Ave, Sacramento, CA 95825. The listed phone number is (916) 973-5000.
What is Alan Williams's specialty?
The primary specialty registered for this NPI is Neurological Surgery with taxonomy code 207T00000X.
Is Alan Williams enrolled in Medicare?
Yes. Alan Williams is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Alan Williams's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Alan Williams reassigns Medicare benefits to Permanente Medical Group Inc (Stockton, CA). The 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 Alan Williams'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 Alan Williams 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.