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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 30 days.

DR. LEONARD I LEVEN M.D.
NPI 1821098245
Psychiatry & Neurology - Child & Adolescent Psychiatry in Old Greenwich, CT

Active since July 28, 2005PECOS Enrolled
3 W END AVE, OLD GREENWICH, CT 06870(203) 637-1486(203) 637-1486 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: July 26, 2026.

Record update history: Jul 13, 2026, Sep 11, 2025 (2 updates tracked since 2025).

About Dr. Leonard I Leven M.d. NPPES

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

DR. LEONARD I LEVEN M.D. (NPI 1821098245) is an individual child & adolescent psychiatry provider in Old Greenwich, Connecticut, licensed in New York (167310) and active in the NPI registry since July 2005. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1821098245
Entity TypeIndividualMale
Primary Taxonomy2084P0804X
Provider Legal NameDR. LEONARD I LEVENCredential: M.D.
Location Address3 W END AVEOld Greenwich, CT 06870-1640
Mailing Address3 Bayberry RdElmsford, NY 10523-1701 · (914) 347-4510 · Fax (914) 347-5020
Phone(203) 637-1486
Fax(203) 637-1486
Sole ProprietorNo
Enumeration DateJuly 28, 2005
Last NPPES UpdateJuly 13, 20262 updates tracked since enumeration
✔ NPI 1821098245 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyPsychiatry & Neurology · Child & Adolescent PsychiatryAllopathic & Osteopathic Physicians
Taxonomy Code2084P0804X
Licenses✔ Licensed in NY · 167310✔ Licensed in CT · 026744
Definition

Child & Adolescent Psychiatry is a subspecialty of psychiatry with additional skills and training in the diagnosis and treatment of developmental, behavioral, emotional, and mental disorders of childhood and adolescence.

Also ListedPsychiatry & Neurology · PsychiatryTaxonomy 2084P0800X · License 026744 (CT), 167310 (NY)
3 W END AVE, Old Greenwich, CT 06870
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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Leonard I Leven M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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.

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.

LAURA ELIZABETH DERMER LCSW
Social Worker (Clinical)
3 W END AVE
OLD GREENWICH, CT 06870
Western Connecticut Planning Region (203) 536-6555
MACKENZIE FAMILY THERAPY PLLC
Marriage & Family Therapist
3 W END AVE
OLD GREENWICH, CT 06870
Western Connecticut Planning Region (203) 722-5152
JOANNA MACKENZIE
Marriage & Family Therapist
3 W END AVE
OLD GREENWICH, CT 06870
Western Connecticut Planning Region (203) 722-5152

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 Leonard Leven's NPI number?

The NPI number for Leonard Leven is 1821098245. It was assigned to this individual provider in the NPPES registry on July 28, 2005.

Where is Leonard Leven located?

Leonard Leven practices at 3 W End Ave, Old Greenwich, CT 06870. The listed phone number is (203) 637-1486.

What is Leonard Leven's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Child & Adolescent Psychiatry, with taxonomy code 2084P0804X.

Is Leonard Leven enrolled in Medicare?

Yes. Leonard Leven is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Leonard Leven was last updated on July 13, 2026. NPI Profile syncs with the weekly NPPES data releases published by CMS.