DR. THEODORE SETH THOMAS MD
NPI 1326359837
Internal Medicine - Medical Oncology in Saint Louis, MO
About Dr. Theodore Seth Thomas Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. THEODORE SETH THOMAS MD (NPI 1326359837) is an individual medical oncology provider in Saint Louis, Missouri, licensed in Illinois (036166718) and active in the NPI registry since June 2010. He is enrolled in Medicare PECOS, is affiliated with Memorial Hospital, and maintains a secondary practice location in Shiloh.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Location 1
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 and accepts Medicare assignment
Dr. Theodore Seth Thomas 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
2Medicare enrollment records show Theodore Thomas reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Saint Louis, MO 63108
- Reassigned Medicare billing, Illinois enrollment
- 530 clinicians in this Medicare group
Saint Louis, MO 63110
- Reassigned Medicare billing, Missouri enrollment
- 1,133 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 4
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.
Hospital Affiliations CMS Care Compare 2
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Memorial Hospital
Acute Care Hospitals · Belleville, ILBarnes Jewish Hospital
Acute Care Hospitals · Saint Louis, MOPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 63106 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.
SAINT LOUIS, MO 63106
SAINT LOUIS, MO 63106
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 Theodore Thomas's NPI number?
The NPI number for Theodore Thomas is 1326359837. It was assigned to this individual provider in the NPPES registry on June 30, 2010.
Where is Theodore Thomas located?
Theodore Thomas practices at 915 N Grand Blvd, Saint Louis, MO 63106. The listed phone number is (314) 652-4100.
What is Theodore Thomas's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Medical Oncology, with taxonomy code 207RX0202X.
Is Theodore Thomas enrolled in Medicare?
Yes. Theodore Thomas 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 Theodore Thomas's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Theodore Thomas reassigns Medicare benefits to 2 organizations: Washington University Physicians In Illinois, Inc (Saint Louis, MO) and Washington University (Saint Louis, MO). 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 Theodore Thomas's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
Is Theodore Thomas affiliated with any hospitals?
According to CMS data, Theodore Thomas is affiliated with Memorial Hospital and Barnes Jewish Hospital.
When was this NPI record last updated?
The NPPES record for Theodore Thomas was last updated on February 3, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 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. Theodore Seth Thomas, MD · NPI 1326359837
Medical Oncology physician in Saint Louis, Missouri. Individual provider, active in the CMS NPPES registry since June 30, 2010.
## Identity
- **NPI:** 1326359837 (Entity type: Individual)
- **Enumerated:** June 30, 2010
- **Primary specialty:** Internal Medicine - Medical Oncology · taxonomy 207RX0202X
- **State license:** 036166718 (Illinois)
- **Sole proprietor:** No
## Practice location
- **Address:** 915 N GRAND BLVD, Saint Louis, MO 63106-1621
- **Phone:** (314) 652-4100
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Washington University Physicians In Illinois, Inc (NPI 1174015515, Saint Louis, MO); Washington University (NPI 1992746903, Saint Louis, MO) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Missouri, Columbia School Of Medicine, class of 2010
## Record status
- **NPPES last updated:** February 3, 2026
- **Other identifiers:** Medicaid 200008314 (MO)
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Source: [NPI Profile](https://npiprofile.com/npi/1326359837) · Data from the CMS NPPES public registry.