William Hasson, M.D.
NPI 1235662677 · Family Medicine Physician · Napa, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Hasson, M.D. is a Family Medicine Physician provider in Napa, CA (NPI 1235662677).
Provider details
- NPI number
- 1235662677
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- A169243 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
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 · 86 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 435 | 165 |
| Lisinopril | 227 | 76 |
| Levothyroxine Sodium | 195 | 68 |
| Losartan Potassium | 182 | 69 |
| Amlodipine Besylate | 161 | 64 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 160 | 28 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2017-04-04
- Last updated
- 2022-04-12
- Certified
- 2022-04-12
Frequently asked questions
- What is William Hasson's NPI number?
- William Hasson's National Provider Identifier (NPI) is 1235662677, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Hasson's specialty?
- William Hasson is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William Hasson located?
- William Hasson's practice location on file with NPPES is 3285 Claremont Way, Napa, CA 94558-3313.
- What is William Hasson's phone number?
- The practice phone number listed in the NPPES registry for William Hasson is (707) 258-2500.
- Does William Hasson accept Medicare?
- William Hasson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Hasson's NPI active?
- Yes — William Hasson's NPI (1235662677) is active in the NPPES registry as of the last update on 2022-04-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.