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MICHAEL HARRIS NATHANSON MD
NPI 1437132230
Internal Medicine - Gastroenterology in New Haven, CT

Active since November 25, 2005PECOS EnrolledAccepts Medicare Assignment
73.56/100
CMS Quality Rating
15 YORK ST, NEW HAVEN, CT 06510(203) 785-4138(203) 737-1345 Get Directions Write a Review

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

About Michael Harris Nathanson Md NPPES

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

MICHAEL HARRIS NATHANSON MD (NPI 1437132230) is an individual gastroenterology provider in New Haven, Connecticut, licensed in Connecticut (029365) and active in the NPI registry since November 2005. He is enrolled in Medicare PECOS, maintains a secondary practice location in Boca Raton, and is a graduate of Other (1985).

NPPES Registry Identity

NPI1437132230
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameMICHAEL HARRIS NATHANSONCredential: MD
Location Address15 YORK STNew Haven, CT 06510-3221
Mailing Address15 York St, Lmp - 180New Haven, CT 06510-3221 · (203) 785-4138 · Fax (203) 737-1345
Phone(203) 785-4138
Fax(203) 737-1345
Sole ProprietorNo
Medical School CMSOtherGraduated 1985
Enumeration DateNovember 25, 2005
Last NPPES UpdateApril 2, 2026
NPPES CertifiedApril 2, 2026
✔ NPI 1437132230 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
Licenses✔ Licensed in CT · 029365✔ Licensed in FL · ME158547
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
15 YORK ST, New Haven, CT 06510
Open in Google Maps ↗

Secondary Practice Location 1

Location 14805 NW 2nd AveBoca Raton, FL 33431-4141 · Phone (561) 961-0208

Other Identifiers 2

Medicaid001293654CT
Medicaid129020000FL

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Michael Harris Nathanson Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID244368884
PECOS Enrollment IDI20100503000382
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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 06510 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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

73.56/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality75.84
Promoting Interoperability74
Improvement Activities40
Cost51.43

Other Providers at the Same Location NPPES 20

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

KARAM AL JUMAILY
Student in an Organized Health Care Education/Training Program
15 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-4668
AARON VASSALL M.D.
Student in an Organized Health Care Education/Training Program
15 YORK ST, YNHH DEPT OF MEDICINE, LMP 1092
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-5555
MS. PEGGY SUEJIN MYUNG M.D., PH.D.
Dermatology (Dermatopathology)
15 YORK ST, LMP 5031
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (215) 668-7559
ROBERT E TIGELAAR MD
Dermatology
15 YORK ST, DERMATOLOGY, LCI ROOM 609
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-4632
REBECCA SLOTKIN M.D.
Internal Medicine
15 YORK ST, YNHH DEPT OF MEDICINE, LMP 1092
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-5555
MICHAEL GIRARDI MD
Dermatology
15 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-4632
GERALD H FRIEDLAND MD
Internal Medicine (Infectious Disease)
15 YORK ST, NATHAN SMITH BUILDING
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-5303
KACIE R CARLSON PA-C
Physician Assistant
15 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-4632

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 Michael Nathanson's NPI number?

The NPI number for Michael Nathanson is 1437132230. It was assigned to this individual provider in the NPPES registry on November 25, 2005.

Where is Michael Nathanson located?

Michael Nathanson practices at 15 York St, New Haven, CT 06510. The listed phone number is (203) 785-4138.

What is Michael Nathanson's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Michael Nathanson enrolled in Medicare?

Yes. Michael Nathanson is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

When was this NPI record last updated?

The NPPES record for Michael Nathanson was last updated on April 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.