William Mao, PHARMD
NPI 1902979297 · Pharmacist · Fontana, CA
William Mao, PHARMD is a Pharmacist provider in Fontana, CA (NPI 1902979297).
Provider details
- NPI number
- 1902979297
- Entity type
- Individual
- Primary specialty
- PharmacistPharmacy Service Providers
- Credential
- PHARMD
- Sex
- Male
- Sole proprietor
- No
- License
- 55067 (CA)
Specialties & taxonomies
Pharmacy Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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 · 2 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Metformin Hclbrand: Metformin Hcl Er | 31 | 24 |
| Semaglutidebrand: Ozempic | 12 | — |
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
- 2006-11-16
- Last updated
- 2007-07-08
Frequently asked questions
- What is William Mao's NPI number?
- William Mao's National Provider Identifier (NPI) is 1902979297, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Mao's specialty?
- William Mao is listed in the NPPES registry with a primary specialty of Pharmacist (Pharmacy Service Providers).
- Where is William Mao located?
- William Mao's practice location on file with NPPES is 9985 Sierra Ave, Fontana, CA 92335-6720.
- What is William Mao's phone number?
- The practice phone number listed in the NPPES registry for William Mao is (909) 427-7364.
- Is William Mao's NPI active?
- Yes — William Mao's NPI (1902979297) 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.