William R. Mao, PHARMD
Pharmacist · Fontana, CA
William R. Mao, PHARMD is a pharmacist with a practice address in Fontana, California, and NPI 1902979297, issued on Nov 16, 2006. Check the license (California 55067, as entered in NPPES) with the California board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- William R. Mao
- Credential
- PHARMD
- Primary taxonomy
- Pharmacist 183500000X
- License number
- 55067 CA
Self-reported in NPPES; status is on the state search - Practice location
- 9985 Sierra Ave, Fontana, CA 92335
- Phone
- (909) 427-7364
- Enumerated
- Nov 16, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest pharmacist records → All 32,533 in California → Look up another NPI →
Also registered at 9985 Sierra Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify William R. Mao in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license 55067Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
37% fewer Medicare Part D claims than the average pharmacist in 2024
75 Medicare Part D claims for 49 beneficiaries, against an average of 119 among the 28,524 providers of this specialty who prescribed in Part D.
Most prescribed
- Metformin Hcl Er31 claims
- Ozempic12 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
William R. Mao among 32,533 pharmacist records in California
William R. Mao, PHARMD is one of 32,533 pharmacist records with a practice address in California. 15% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than under 1% of them.
- NPI issued2006 · under 1% of these records are older, 94% newer
- In a Medicare fileYes · 15% of these records are
- In the CMS Doctors and Clinicians fileNo · under 1% of these records are
- Record last updated2007 · 76% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 183500000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
227 pharmacist records list a practice address in Fontana
They are 227 of the 3,012 NPPES records with a practice address in Fontana, and 32,533 pharmacist records in California.
All 32,533 in California → Every provider in Fontana → Pharmacist nationwide →
The 8 pharmacist records with the nearest ZIP codes
- Gabriel Alvarez, PHARM.D.Fontana, CA 923351689774440
- Julie Chae, R.PH.Fontana, CA 923351477644102
- Francis Chan, PHARM.D.Fontana, CA 923351114028339
- Patrick Chang, PHARM DFontana, CA 923351538250238
- Jerry Cole, RPHFontana, CA 923351437178365
- Phyllip Dedden, PHARM.D.Fontana, CA 923351780775478
- Therese Hershey, PHARM.D.Fontana, CA 923351730280868
- David Kim, PHARMDFontana, CA 923351720170640
Common questions
What is William R. Mao, PHARMD's NPI number?
William R. Mao, PHARMD's National Provider Identifier (NPI) is 1902979297, issued on Nov 16, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William R. Mao, PHARMD located?
The NPPES record lists a practice address at 9985 Sierra Ave, Fontana, CA, 92335. Phone: (909) 427-7364. Providers update this record themselves, so call before visiting.
How can I verify William R. Mao, PHARMD's license?
NPPES lists California license number 55067, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.
How much does William R. Mao, PHARMD prescribe under Medicare Part D?
In 2024, William R. Mao, PHARMD had 75 Medicare Part D claims for 49 beneficiaries; the average among pharmacist prescribers was 119. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.