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Clinical Psychologist

Matthew Messier, PSY

Sees patients in Ewa Beach, HI · Hawaii

Summary

Matthew Messier, PSY (Clinical Psychologist) is enrolled with Medicare at 1 practice location in Ewa Beach, HI. NPI 1811726110. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Matthew Messier, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Clinical PsychologistPrimary specialty
YesAccepts Medicare assignment
3Years since medical school (graduated 2023)
MaleGender (as listed)
Waianae District Comprehensive Health and Hospital Board IncorporatedGroup practice

Quick answers

Where does Matthew Messier see patients?
Medicare's clinician data lists 1 practice location in Ewa Beach, HI. Call before your visit to confirm the address.
What is Matthew Messier's specialty?
Medicare lists Clinical Psychologist as the primary specialty.
Does Matthew Messier accept Medicare assignment?
Yes. Medicare's clinician data says Matthew Messier accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Matthew Messier?
(808) 697-3281, as listed in official Medicare / NPI Registry data.
What is Matthew Messier's NPI number?
1811726110. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Matthew Messier is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Matthew Messier as a member of this group (CMS data updated 2026-10-02).

  • Waianae District Comprehensive Health and Hospital Board Incorporated162 clinicians in the group

Specialties

Find other clinicians: Clinical Psychologist, Hawaii →

Other clinical psychologists in Ewa Beach

Clinicians with the same Medicare primary specialty in Ewa Beach, HI — not a recommendation.

All clinical psychologists in Ewa Beach →

Clinician information

CredentialPSY
Graduation year2023
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1811726110
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians