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DR. WILLIAM MACK SHANNON PH.D.
NPI 1063668275
Psychologist - Clinical in Oakland, CA

Active since August 07, 2008PECOS EnrolledAccepts Medicare Assignment
625 16TH ST UNIT 401, OAKLAND, CA 94612(510) 290-6203 Get Directions Write a Review

NPPES record last updated: September 27, 2024. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. William Mack Shannon Ph.d. NPPES

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

DR. WILLIAM MACK SHANNON PH.D. (NPI 1063668275) is an individual clinical provider in Oakland, California, licensed in California (PSY22103) and active in the NPI registry since August 2008. He is enrolled in Medicare PECOS and is a graduate of Other (1991).

NPPES Registry Identity

NPI1063668275
Entity TypeIndividualMale
Primary Taxonomy103TC0700X
Provider Legal NameDR. WILLIAM MACK SHANNONCredential: PH.D.
Location Address625 16TH ST UNIT 401Oakland, CA 94612-2180
Mailing Address625 16th St Unit 401Oakland, CA 94612-2180 · (619) 817-9309
Phone(510) 290-6203
Sole ProprietorYes
Medical School CMSOtherGraduated 1991
Enumeration DateAugust 7, 2008
Last NPPES UpdateSeptember 27, 2024
NPPES CertifiedSeptember 27, 2024
✔ NPI 1063668275 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychologist · ClinicalBehavioral Health & Social Service Providers
Taxonomy Code103TC0700X
License✔ Licensed in CA · PSY22103
Definition
A psychologist who provides continuing and comprehensive mental and behavioral health care for individuals and families; consultation to agencies and communities; training, education and supervision; and research-based practice. It is a specialty in breadth -- one that is broadly inclusive of severe psychopathology -- and marked by comprehensiveness and integration of knowledge and skill from a broad array of disciplines within and outside of psychology proper. The scope of clinical psychology encompasses all ages, multiple diversities and varied systems.
625 16TH ST UNIT 401, Oakland, CA 94612
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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 and accepts Medicare assignment

Dr. William Mack Shannon Ph.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 ID9638204761
PECOS Enrollment IDI20100315000885
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 Shannon reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Ehab Yacoub MD Inc.
352 mi
Child & Adolescent Psychiatry
1225 W 190TH ST STE 280
Gardena, CA 90248
  • Reassigned Medicare billing, California enrollment
  • 375 clinicians in this Medicare group
NPI 1417373713 (310) 515-8113

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 94612 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
$202.35 typical visit price
range $69.00 – $202.35
Typical copayment $50.58 (range $17.25 – $50.58)
Most-billed visit code 99205
Established Patient
$119.48 typical visit price
range $23.44 – $166.46
Typical copayment $29.87 (range $5.86 – $41.61)
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.

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 Shannon's NPI number?

The NPI number for William Shannon is 1063668275. It was assigned to this individual provider in the NPPES registry on August 7, 2008.

Where is William Shannon located?

William Shannon practices at 625 16th St Unit 401, Oakland, CA 94612. The listed phone number is (510) 290-6203.

What is William Shannon's specialty?

The primary specialty registered for this NPI is Psychologist, specializing in Clinical, with taxonomy code 103TC0700X.

Is William Shannon enrolled in Medicare?

Yes. William Shannon 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.

Which organization bills Medicare for William Shannon's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Shannon reassigns Medicare benefits to Ehab Yacoub MD Inc. (Gardena, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Shannon's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for William Shannon was last updated on September 27, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.