William Holmes, M.D.
NPI 1639348246 · Psychiatry Physician · Austin, TX
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Holmes, M.D. is a Psychiatry Physician provider in Austin, TX (NPI 1639348246).
Provider details
- NPI number
- 1639348246
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- H4418 (TX)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
18 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
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 prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 5 distinct drugs on file.
| Drug | Part D claims (2024) |
|---|---|
| Dextroamphetamine/Amphetaminebrand: Dextroamphetamine-Amphet Er | 47 |
| Dextroamphetamine/Amphetaminebrand: Dextroamphetamine-Amphetamine | 33 |
| Lisdexamfetamine Dimesylatebrand: Vyvanse | 15 |
| Alprazolam | 13 |
| Lorazepam | 13 |
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
- 2008-02-27
- Last updated
- 2013-10-11
Frequently asked questions
- What is William Holmes's NPI number?
- William Holmes's National Provider Identifier (NPI) is 1639348246, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Holmes's specialty?
- William Holmes is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is William Holmes located?
- William Holmes's practice location on file with NPPES is 12515 Research Blvd, Austin, TX 78759-2228.
- What is William Holmes's phone number?
- The practice phone number listed in the NPPES registry for William Holmes is (210) 241-2691.
- Does William Holmes accept Medicare?
- William Holmes is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Holmes's NPI active?
- Yes — William Holmes's NPI (1639348246) is active in the NPPES registry as of the last update on 2013-10-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.