WALTER THOMAS MD A MEDICAL CORPORATION
NPI 1598953358
Family Medicine - Addiction Medicine in Simi Valley, CA
About Walter Thomas Md A Medical Corporation NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WALTER THOMAS MD A MEDICAL CORPORATION (NPI 1598953358) is a healthcare organization registered as an addiction medicine in Simi Valley, California and active in the NPI registry since October 2007. The organization holds a CLIA Waiver certificate valid through August 31, 2028 and lists Walter Thomas, M.d., as its authorized official.
NPPES Registry Identity
Specialties & Licenses
Group Practice 1
Medicare Participation & PECOS CMS
Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Walter Thomas Md A Medical Corporation is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Clinicians Billing Medicare Through This Organization
2Medicare enrollment records show 2 clinicians reassign Medicare billing to Walter Thomas MD A Medical Corporation, which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.
Clinicians, nearest first (2)
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
CLIA Laboratory Certificates CMS CLIA
Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.
Certificate of Waiver 05D0584165
Walter Thomas MD · Simi Valley, CAFrequently 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 Walter Thomas MD A Medical Corporation's NPI number?
The NPI number for Walter Thomas MD A Medical Corporation is 1598953358. It was assigned to this organization in the NPPES registry on October 5, 2007.
Where is Walter Thomas MD A Medical Corporation located?
Walter Thomas MD A Medical Corporation is located at 1980 Sequoia Ave, Simi Valley, CA 93063. The listed phone number is (805) 527-1804.
What is Walter Thomas MD A Medical Corporation's specialty?
The primary specialty registered for this NPI is Family Medicine, specializing in Addiction Medicine, with taxonomy code 207QA0401X.
Is Walter Thomas MD A Medical Corporation enrolled in Medicare?
Yes. Walter Thomas MD A Medical Corporation is registered in the Medicare PECOS enrollment system.
How many clinicians bill Medicare through Walter Thomas MD A Medical Corporation?
According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians reassign their Medicare billing to Walter Thomas MD A Medical Corporation, in Family Practice and General Practice. A 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 the clinician's services. Of these, 2 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Does Walter Thomas MD A Medical Corporation hold a CLIA laboratory certificate?
Yes. A Certificate of Waiver (number 05D0584165) is associated with this NPI, valid through August 31, 2028. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.
When was this NPI record last updated?
The NPPES record for Walter Thomas MD A Medical Corporation was last updated on December 17, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.
# Walter Thomas Md A Medical Corporation · NPI 1598953358
Addiction Medicine organization in Simi Valley, California. Organization record, active in the CMS NPPES registry since October 5, 2007.
## Identity
- **NPI:** 1598953358 (Entity type: Organization)
- **Enumerated:** October 5, 2007
- **Primary specialty:** Family Medicine - Addiction Medicine · taxonomy 207QA0401X
- **Organization subpart:** No
- **Authorized official:** Walter Thomas, M.D.
## Practice location
- **Address:** 1980 SEQUOIA AVE, Simi Valley, CA 93063-3167
- **Phone:** (805) 527-1804 · **Fax:** (805) 527-5241
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Clinicians billing through this organization:** 2 clinicians in 2 Medicare specialties reassign Medicare billing to this organization (form CMS-855R); largest: Family Practice (1), General Practice (1); 2 practice at this address · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** December 17, 2019
- **CLIA laboratory certificates:** 1 on file
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Source: [NPI Profile](https://npiprofile.com/npi/1598953358) · Data from the CMS NPPES public registry.