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DR. WILLIAM DALE HASSON II M.D.
NPI 1235662677
Family Medicine in Napa, CA

Active since April 04, 2017PECOS EnrolledAccepts Medicare Assignment
3285 CLAREMONT WAY, NAPA, CA 94558(707) 258-2500 Get Directions Write a Review

NPPES record last updated: April 12, 2022. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Apr 12, 2022, Dec 17, 2021 (2 updates tracked since 2021).

About Dr. William Dale Hasson Ii M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. WILLIAM DALE HASSON II M.D. (NPI 1235662677) is an individual family medicine provider in Napa, California, licensed in California (A169243) and active in the NPI registry since April 2017. He is enrolled in Medicare PECOS and is a graduate of Florida International Univ, College Of Medicine (2017).

NPPES Registry Identity

NPI1235662677
Entity TypeIndividualMale
Primary Taxonomy207Q00000X
Provider Legal NameDR. WILLIAM DALE HASSON IICredential: M.D.
Location Address3285 CLAREMONT WAYNapa, CA 94558-3313
Mailing Address3285 Claremont WayNapa, CA 94558-3313 · (707) 258-2500
Phone(707) 258-2500
Sole ProprietorNo
Medical School CMSFlorida International Univ, College Of MedicineGraduated 2017
Enumeration DateApril 4, 2017
Last NPPES UpdateApril 12, 20222 updates tracked since enumeration
NPPES CertifiedApril 12, 2022
✔ NPI 1235662677 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in CA · A169243
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
3285 CLAREMONT WAY, Napa, CA 94558
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. William Dale Hasson Ii M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID6002223286
PECOS Enrollment IDI20210406001612
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94558 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$98.97 typical visit price
range $65.08 – $192.16
Typical copayment $24.74 (range $16.27 – $48.04)
Most-billed visit code 99203
Established Patient
$113.15 typical visit price
range $21.86 – $157.83
Typical copayment $28.28 (range $5.46 – $39.45)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. SELINA MARIE MARTINEZ DO
Family Medicine
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-2500
LAWRENCE A. LIPPMANN MD
Family Medicine
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-2500
MARVIN D. SAKAKIHARA MD
Internal Medicine
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-2500
JEAN YOSHIOKA M.D.
Family Medicine
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-2500
DR. KENNETH ALLAN MILES OD
Optometrist
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-4507
MARIA ESPINO
Pharmacist
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-4440
JACK TANG
Pharmacist
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-4484
KAISER FOUNDATION HEALTH PLAN INC
Pharmacy (Community/Retail Pharmacy)
3285 CLAREMONT WAY
NAPA, CA 94558
Napa County (707) 258-4526

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Hasson's NPI number?

The NPI number for William Hasson is 1235662677. It was assigned to this individual provider in the NPPES registry on April 4, 2017.

Where is William Hasson located?

William Hasson practices at 3285 Claremont Way, Napa, CA 94558. The listed phone number is (707) 258-2500.

What is William Hasson's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is William Hasson enrolled in Medicare?

Yes. William Hasson is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

When was this NPI record last updated?

The NPPES record for William Hasson was last updated on April 12, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.