DR. OLIVIA ANNA JEAN BEGASSE DE DHAEM M.D.
NPI 1639557408
Psychiatry & Neurology - Neurology in Stamford, CT

Q: What is Olivia Begasse De Dhaem's NPI number?

The NPI number for Olivia Begasse De Dhaem is 1639557408. It was assigned to this individual provider in the NPPES registry on May 13, 2015.

Q: What is Olivia Begasse De Dhaem's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Neurology, with taxonomy code 2084N0400X.

Q: Is Olivia Begasse De Dhaem enrolled in Medicare?

No. Olivia Begasse De Dhaem has opted out of Medicare through April 1, 2027. Care is provided under private contracts, and Medicare does not pay for services furnished by providers who have opted out. The provider remains eligible to order and refer services for Medicare patients.

Active since May 13, 2015Opted out of Medicare · through Apr 1, 2027

90 MOGAN STREET, SUITE 305-306, STAMFORD, CT 06902(203) 306-2949(203) 884-8939 Get Directions Write a Review

NPPES record last updated: February 2, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Feb 2, 2026, Jan 19, 2022, Oct 6, 2020 and 1 more (4 updates tracked since 2019).

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About Dr. Olivia Anna Jean Begasse De Dhaem M.d. NPPES

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

DR. OLIVIA ANNA JEAN BEGASSE DE DHAEM M.D. (NPI 1639557408) is an individual neurology provider in Stamford, Connecticut, licensed in Connecticut (64919) and active in the NPI registry since May 2015. She has opted out of Medicare through April 1, 2027 and remains eligible to order and refer.

NPPES Registry Identity

NPI1639557408

Entity TypeIndividualFemale

Primary Taxonomy2084N0400X

Provider Legal NameDR. OLIVIA ANNA JEAN BEGASSE DE DHAEMCredential: M.D.

Location Address90 MOGAN STREET, SUITE 305-306Stamford, CT 06902

Mailing Address90 Mogan Street, Suite 305-306Stamford, CT 06902 · (203) 306-2949 · Fax (203) 884-8939

Phone(203) 306-2949

Fax(203) 884-8939

Sole ProprietorYes

Enumeration DateMay 13, 2015

Last NPPES UpdateFebruary 2, 20264 updates tracked since enumeration

NPPES CertifiedFebruary 2, 2026

✔ NPI 1639557408 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychiatry & Neurology · NeurologyAllopathic & Osteopathic Physicians

Taxonomy Code2084N0400X

Licenses✔ Licensed in CT · 64919✔ Licensed in MA · 277815

Definition

A Neurologist specializes in the diagnosis and treatment of diseases or impaired function of the brain, spinal cord, peripheral nerves, muscles, autonomic nervous system, and blood vessels that relate to these structures.

90 MOGAN STREET, Stamford, CT 06902

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

ⓘ

Opted out of Medicare

Dr. Olivia Anna Jean Begasse De Dhaem M.d. has filed a Medicare opt-out affidavit. Services are provided under private contract between the provider and the patient, and are not billed to or reimbursed by Medicare. The opt-out is on file from April 1, 2025 through April 1, 2027.

Opt-Out Effective DateApril 1, 2025

Opt-Out In Effect ThroughApril 1, 2027Opt-out affidavits renew automatically every two years unless cancelled

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesAn opted-out provider can still order and refer for Medicare patients in the categories marked above, even though their own services are not covered.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 06902 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

$138.84 typical visit price

range $60.82 – $183.10

Typical copayment $34.71 (range $15.20 – $45.77)

Most-billed visit code 99204

Established Patient

$106.68 typical visit price

range $19.76 – $149.26

Typical copayment $26.67 (range $4.94 – $37.31)

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 Olivia Begasse De Dhaem's NPI number?

The NPI number for Olivia Begasse De Dhaem is 1639557408. It was assigned to this individual provider in the NPPES registry on May 13, 2015.

Where is Olivia Begasse De Dhaem located?

Olivia Begasse De Dhaem practices at 90 Mogan Street Suite 305-306, Stamford, CT 06902. The listed phone number is (203) 306-2949.

What is Olivia Begasse De Dhaem's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Neurology, with taxonomy code 2084N0400X.

Is Olivia Begasse De Dhaem enrolled in Medicare?

No. Olivia Begasse De Dhaem has opted out of Medicare through April 1, 2027. Care is provided under private contracts, and Medicare does not pay for services furnished by providers who have opted out. The provider remains eligible to order and refer services for Medicare patients.

When was this NPI record last updated?

The NPPES record for Olivia Begasse De Dhaem was last updated on February 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.