Mark Williamson, DDS
NPI 1851844260 · General Practice Dentistry · San Antonio, TX
Enrolled with Medicare as Order and Referring Only - Dentist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Williamson, DDS is a General Practice Dentistry provider in San Antonio, TX (NPI 1851844260).
Provider details
- NPI number
- 1851844260
- Entity type
- Individual
- Primary specialty
- General Practice DentistryDental Providers
- Credential
- DDS
- Sex
- Male
- Sole proprietor
- No
- License
- 32216 (TX)
Specialties & taxonomies
Dental Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
9 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 · 1 distinct drug on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Amoxicillin | 42 | 33 |
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
- 2016-08-02
- Last updated
- 2026-04-29
- Certified
- 2026-04-29
Frequently asked questions
- What is Mark Williamson's NPI number?
- Mark Williamson's National Provider Identifier (NPI) is 1851844260, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Williamson's specialty?
- Mark Williamson is listed in the NPPES registry with a primary specialty of General Practice Dentistry (Dental Providers).
- Where is Mark Williamson located?
- Mark Williamson's practice location on file with NPPES is 3355 Cherry Ridge St Ste 216, San Antonio, TX 78230-4818.
- What is Mark Williamson's phone number?
- The practice phone number listed in the NPPES registry for Mark Williamson is (210) 341-2569.
- Does Mark Williamson accept Medicare?
- Mark Williamson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Williamson's NPI active?
- Yes — Mark Williamson's NPI (1851844260) is active in the NPPES registry as of the last update on 2026-04-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.