WILLIAM DUAN MD
NPI 1881334308
Psychiatry & Neurology - Psychiatry in Atascadero, CA

Q: What is William Duan's NPI number?

The NPI number for William Duan is 1881334308. It was assigned to this individual provider in the NPPES registry on March 31, 2022.

Q: What is William Duan's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Psychiatry, with taxonomy code 2084P0800X.

Q: When was this NPI record last updated?

The NPPES record for William Duan was last updated on August 10, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 months 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.

Active since March 31, 2022PECOS Enrolled

10333 EL CAMINO REAL, ATASCADERO, CA 93422(805) 468-2000 Get Directions Write a Review

NPPES record last updated: August 10, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Aug 10, 2026, Apr 24, 2026, Mar 19, 2026 (3 updates tracked since 2026).

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About William Duan Md NPPES

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

WILLIAM DUAN MD (NPI 1881334308) is an individual psychiatry provider in Atascadero, California, licensed in California (A189333) and active in the NPI registry since March 2022. He is enrolled in Medicare PECOS and is a graduate of Other (2022).

NPPES Registry Identity

NPI1881334308

Entity TypeIndividualMale

Primary Taxonomy2084P0800X

Provider Legal NameWILLIAM DUANCredential: MD

Location Address10333 EL CAMINO REALAtascadero, CA 93422-5808

Mailing Address10333 El Camino RealAtascadero, CA 93422-5808 · (805) 468-2000

Phone(805) 468-2000

Sole ProprietorNo

Medical School CMSOtherGraduated 2022

Enumeration DateMarch 31, 2022

Last NPPES UpdateAugust 10, 20263 updates tracked since enumeration

NPPES CertifiedAugust 10, 2026

✔ NPI 1881334308 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychiatry & Neurology · PsychiatryAllopathic & Osteopathic Physicians

Taxonomy Code2084P0800X

License✔ Licensed in CA · A189333

Definition

A Psychiatrist specializes in the prevention, diagnosis, and treatment of mental disorders, emotional disorders, psychotic disorders, mood disorders, anxiety disorders, substance-related disorders, sexual and gender identity disorders and adjustment disorders. Biologic, psychological, and social components of illnesses are explored and understood in treatment of the whole person. Tools used may include diagnostic laboratory tests, prescribed medications, evaluation and treatment of psychological and interpersonal problems with individuals and families, and intervention for coping with stress, crises, and other problems.

10333 EL CAMINO REAL, Atascadero, CA 93422

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

William Duan Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID42782989

PECOS Enrollment IDI20260611003232

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.

Medicare Billing Reassignment

Medicare enrollment records show William Duan reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

County Of Santa Clara

119 mi

Federally Qualified Health Center (FQHC)

7475 CAMINO ARROYO
Gilroy, CA 95020

Reassigned Medicare billing, California enrollment
2,460 clinicians in this Medicare group

NPI 1922093533 (408) 885-5000

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 93422 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

$178.89 typical visit price

range $59.84 – $178.89

Typical copayment $44.72 (range $14.96 – $44.72)

Most-billed visit code 99205

Established Patient

$74.24 typical visit price

range $19.70 – $146.55

Typical copayment $18.56 (range $4.92 – $36.63)

Most-billed visit code 99213

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.

GIZELLA MARIA RAYMOND N.P., R.N.

Nurse Practitioner (Psychiatric/Mental Health)