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DEMARIE M OLU-WILLIAMS D.O
NPI 1841533791
Internal Medicine in Mesa, AZ

Active since March 28, 2013
9124 E MAIN ST STE 20-21, MESA, AZ 85207(480) 295-8070 Get Directions Write a Review

NPPES record last updated: April 8, 2020. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Apr 8, 2020, Sep 23, 2019, Oct 27, 2016 (3 updates tracked since 2016).

About Demarie M Olu-williams D.o NPPES

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

DEMARIE M OLU-WILLIAMS D.O (NPI 1841533791) is an individual internal medicine provider in Mesa, Arizona, licensed in Arizona (008144) and active in the NPI registry since March 2013.

NPPES Registry Identity

NPI1841533791
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameDEMARIE M OLU-WILLIAMSCredential: D.O
Location Address9124 E MAIN ST STE 20-21Mesa, AZ 85207-8700
Mailing Address9124 E Main St, Ste 20-21Mesa, AZ 85207-8700
Phone(480) 295-8070
Sole ProprietorYes
Enumeration DateMarch 28, 2013
Last NPPES UpdateApril 8, 20203 updates tracked since enumeration
NPPES CertifiedApril 8, 2020
✔ NPI 1841533791 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
Licenses✔ Licensed in AZ · 008144✔ Licensed in DE · C2-0011826
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
9124 E MAIN ST STE 20-21, Mesa, AZ 85207
Open in Google Maps ↗

Other Identifiers 1

Other1841533791DE · Npi #

Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Demarie M Olu-williams D.o is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Billing Reassignment

Medicare enrollment records show Demarie Olu-williams reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Tri-County Hospitalists, LLC
2,040 mi
Internal Medicine
507 KIMBERTON RD
Phoenixville, PA 19460
  • Reassigned Medicare billing, Pennsylvania enrollment
  • 74 clinicians in this Medicare group
NPI 1730518564 (484) 429-2351

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

Other Providers at the Same Location NPPES 4

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

MS. CHRISTINA NOEL ROSS FNP-C
Nurse Practitioner (Family)
9124 E MAIN ST STE 20-21
MESA, AZ 85207
Maricopa County (480) 295-8070
DEBRA LYNN STUTZ-MIDDLETON LCSW
Social Worker (Clinical)
9124 E MAIN ST STE 20-21
MESA, AZ 85207
Maricopa County (480) 295-8070
DR. SARAH ELIZABETH STOOKEY PH.D.
Psychologist
9124 E MAIN ST STE 20-21
MESA, AZ 85207
Maricopa County (480) 295-8070
IORA SENIOR HEALTH, LLC
Internal Medicine
9124 E MAIN ST STE 20-21
MESA, AZ 85207
Maricopa County (888) 663-6331

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 Demarie Olu-williams's NPI number?

The NPI number for Demarie Olu-williams is 1841533791. It was assigned to this individual provider in the NPPES registry on March 28, 2013.

Where is Demarie Olu-williams located?

Demarie Olu-williams practices at 9124 E Main St Ste 20-21, Mesa, AZ 85207. The listed phone number is (480) 295-8070.

What is Demarie Olu-williams's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Demarie Olu-williams enrolled in Medicare?

Yes. Demarie Olu-williams is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Demarie Olu-williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Demarie Olu-williams reassigns Medicare benefits to Tri-County Hospitalists, LLC (Phoenixville, PA). 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 Demarie Olu-williams'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 Demarie Olu-williams was last updated on April 8, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.