DR. WILLIAM H. ELLIS PHD
NPI 1942278031
Psychologist in Hyannis, MA

Active since March 14, 2006PECOS EnrolledAccepts Medicare Assignment
218 W MAIN ST, HYANNIS, MA 02601(508) 771-4640(508) 790-4880 Get Directions Write a Review

NPPES record last updated: September 11, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Dr. William H. Ellis Phd NPPES

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

DR. WILLIAM H. ELLIS PHD (NPI 1942278031) is an individual psychologist in Hyannis, Massachusetts, licensed in Massachusetts (2809) and active in the NPI registry since March 2006. He is enrolled in Medicare PECOS and is a graduate of Other (1980).

NPPES Registry Identity

NPI1942278031
Entity TypeIndividualMale
Primary Taxonomy103T00000X
Provider Legal NameDR. WILLIAM H. ELLISCredential: PHD
Location Address218 W MAIN STHyannis, MA 02601-3778
Mailing Address218 W Main StHyannis, MA 02601-3778 · (508) 771-4640 · Fax (508) 790-4880
Fax(508) 790-4880
Sole ProprietorYes
Medical School CMSOtherGraduated 1980
Enumeration DateMarch 14, 2006
Last NPPES UpdateSeptember 11, 2025
NPI 1942278031 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 7

Primary SpecialtyPsychologistBehavioral Health & Social Service Providers
Taxonomy Code103T00000X
License Licensed in MA · 2809
Definition
A psychologist is an individual who is licensed to practice psychology which is defined as the observation, description, evaluation, interpretation, and modification of human behavior by the application of psychological principles, methods, and procedures, for the purpose of preventing or eliminating symptomatic, maladaptive, or undesired behavior and of enhancing interpersonal relationships, work and life adjustment, personal effectiveness, behavioral health, and mental health. The practice of psychology includes, but is not limited to, psychological testing and the evaluation or assessment of personal characteristics, such as intelligence, personality, abilities, interests, aptitudes, and neuropsychological functioning; counseling, psychoanalysis, psychotherapy, hypnosis, biofeedback, and behavior analysis and therapy; diagnosis and treatment of mental and emotional disorder or disability, alcoholism and substance abuse, disorders of habit or conduct, as well as of the psychological aspects of physical illness, accident, injury, or disability; and psycheducational evaluation, therapy, remediation, and consultation. Psychological services may be rendered to individuals, families, groups and the public.
Also ListedPsychologist · Addiction (Substance Use Disorder)Taxonomy 103TA0400X · License 2809 (MA)
Also ListedPsychologist · Adult Development & AgingTaxonomy 103TA0700X · License 2809 (MA)
Also ListedPsychologist · ClinicalTaxonomy 103TC0700X · License 2809 (MA)
Also ListedPsychologist · Clinical Child & AdolescentTaxonomy 103TC2200X · License 2809 (MA)
Also ListedPsychologist · FamilyTaxonomy 103TF0000X · License 2809 (MA)
Also ListedPsychologist · Health ServiceTaxonomy 103TH0100X · License 2809 (MA)

Accepted Insurance

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 H. Ellis Phd 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 ID8224220280
PECOS Enrollment IDI20101008000314
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.

Areas of Expertise CMS Part B claims 2

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Psychotherapy, 45 minutes 90834
Psychotherapy is a treatment method where you converse with a therapist about your thoughts, feelings, and behaviors. In a 45-minute session, the therapist assists you in understanding and managing your mental health concerns, improving emotional wellness, and promoting personal growth.
565 services55 patients
Psychotherapy, 30 minutes 90832
Psychotherapy is a therapeutic interaction or treatment between a trained professional and a patient. In a 30-minute session, the therapist helps you explore feelings, thoughts, and behaviors to better understand yourself and manage life's challenges.
58 services14 patients

Other Providers at the Same Location NPPES 3

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

Psychologist (Health Service)
218 W MAIN ST
HYANNIS, MA 02601
Psychologist (Clinical)
218 W MAIN ST
HYANNIS, MA 02601
Social Worker (Clinical)
218 W MAIN ST
HYANNIS, MA 02601

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 Ellis's NPI number?

The NPI number for William Ellis is 1942278031. It was assigned to this individual provider in the NPPES registry on March 14, 2006.

Where is William Ellis located?

William Ellis practices at 218 W Main St, Hyannis, MA 02601. The listed phone number is (508) 771-4640.

What is William Ellis's specialty?

The primary specialty registered for this NPI is Psychologist with taxonomy code 103T00000X.

Is William Ellis enrolled in Medicare?

Yes. William Ellis 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.

What insurance does William Ellis accept?

Health plans from Anthem Blue Cross and Blue Shield and Harvard Pilgrim Health Care list William Ellis as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for William Ellis was last updated on September 11, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.