William Holloway, MD
NPI 1649396334 · Vascular & Interventional Radiology Physician · Saint Louis, MO
Enrolled with Medicare as Practitioner - Diagnostic Radiology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Holloway, MD is a Vascular & Interventional Radiology Physician provider in Saint Louis, MO (NPI 1649396334).
Provider details
- NPI number
- 1649396334
- Entity type
- Individual
- Primary specialty
- Vascular & Interventional Radiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- 2004028836 (MO)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
2,144 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Ct Scan Head Or Brain Without Contrast70450 | 788 | $37 |
| Mri Scan of Brain Before and After Contrast70553 | 271 | $102 |
| Ct Scan of Upper Spine Without Contrast72125 | 216 | $44 |
| Ct Scan of Lower Spine Without Contrast72131 | 105 | $44 |
| Mri Scan of Lower Spinal Canal Without Contrast72148 | 102 | $67 |
| Ct Scan of Blood Vessels of Head With Contrast70496 | 99 | $77 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 1 distinct drug on file.
| Drug | Part D claims (2024) |
|---|---|
| Clopidogrel Bisulfatebrand: Clopidogrel | 21 |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means no Part D record, never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-22
- Last updated
- 2007-07-08
Frequently asked questions
- What is William Holloway's NPI number?
- William Holloway's National Provider Identifier (NPI) is 1649396334, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Holloway's specialty?
- William Holloway is listed in the NPPES registry with a primary specialty of Vascular & Interventional Radiology Physician (Allopathic & Osteopathic Physicians).
- Where is William Holloway located?
- William Holloway's practice location on file with NPPES is 226 N Boyle Ave Apt 2n, Saint Louis, MO 63108-2922.
- What is William Holloway's phone number?
- The practice phone number listed in the NPPES registry for William Holloway is (314) 535-3601.
- Does William Holloway accept Medicare?
- William Holloway is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Holloway's NPI active?
- Yes — William Holloway's NPI (1649396334) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.