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MARK J. OSTROWSKI, PSY.D. LLC
NPI 1346649589
Psychologist - Clinical in Stamford, CT

Active since August 13, 2014
999 SUMMER ST, SUITE 200, STAMFORD, CT 06905(203) 967-4995(203) 357-9030 Get Directions Write a Review

NPPES record last updated: August 13, 2014. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Mark J. Ostrowski, Psy.d. Llc NPPES

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

MARK J. OSTROWSKI, PSY.D. LLC (NPI 1346649589) is a healthcare organization registered as a clinical in Stamford, Connecticut and active in the NPI registry since August 2014. The organization lists Mark J. Ostrowski, Clinical Psychologist, as its authorized official.

NPPES Registry Identity

NPI1346649589
Entity TypeOrganization
Primary Taxonomy103TC0700X
Legal Business NameMARK J. OSTROWSKI, PSY.D. LLC
Location Address999 SUMMER ST, SUITE 200Stamford, CT 06905-5546
Mailing Address999 Summer St, Suite 200Stamford, CT 06905-5546 · (203) 967-4995 · Fax (203) 357-9030
Phone(203) 967-4995
Fax(203) 357-9030
Organization SubpartNo
Authorized OfficialMark J. OstrowskiClinical Psychologist · (203) 967-4995
Enumeration DateAugust 13, 2014
✔ NPI 1346649589 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 CT · 002433
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.
999 SUMMER ST, Stamford, CT 06905
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Other Identifiers 2

Medicaid008039686CT
Medicare PIN680001539CT

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mark J. Ostrowski, Psy.d. Llc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Mark J. Ostrowski, Psy.D. LLC, which bills Medicare for the services this clinician delivers.

Clinician (1)

Mark Ostrowski, PSY.D.
Clinical Psychologist
NPI 1700022324
999 SUMMER ST SUITE 200
Stamford, CT 06905
(203) 967-4995
✔ PECOS✔ Accepts MedicareSame address

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

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 Mark J. Ostrowski, Psy.D. LLC's NPI number?

The NPI number for Mark J. Ostrowski, Psy.D. LLC is 1346649589. It was assigned to this organization in the NPPES registry on August 13, 2014.

Where is Mark J. Ostrowski, Psy.D. LLC located?

Mark J. Ostrowski, Psy.D. LLC is located at 999 Summer St Suite 200, Stamford, CT 06905. The listed phone number is (203) 967-4995.

What is Mark J. Ostrowski, Psy.D. LLC's specialty?

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

Is Mark J. Ostrowski, Psy.D. LLC enrolled in Medicare?

Yes. Mark J. Ostrowski, Psy.D. LLC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Mark J. Ostrowski, Psy.D. LLC?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Clinical Psychologist) reassigns their Medicare billing to Mark J. Ostrowski, Psy.D. LLC. A 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 the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

What insurance does Mark J. Ostrowski, Psy.D. LLC accept?

Health plans from Anthem Blue Cross and Blue Shield list Mark J. Ostrowski, Psy.D. LLC 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 Mark J. Ostrowski, Psy.D. LLC was last updated on August 13, 2014. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 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.