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CATHERINE MICHELS ALONZO M.D.
NPI 1770802357
Urology in Greenwich, CT

Active since May 22, 2010PECOS Enrolled
73.56/100
CMS Quality Rating
49 LAKE AVE, SUITE 201, GREENWICH, CT 06830(203) 869-1285(203) 737-8035 Get Directions Write a Review

NPPES record last updated: September 12, 2019. Verified against the NPPES registry weekly; last sync: November 08, 2026.

About Catherine Michels Alonzo M.d. NPPES

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

CATHERINE MICHELS ALONZO M.D. (NPI 1770802357) is an individual urology provider in Greenwich, Connecticut, licensed in Connecticut (49084) and active in the NPI registry since May 2010. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1770802357
Entity TypeIndividualFemale
Primary Taxonomy208800000X
Provider Legal NameCATHERINE MICHELS ALONZOCredential: M.D.
Location Address49 LAKE AVE, SUITE 201Greenwich, CT 06830-4501
Mailing Address16 Fox Ridge RdArmonk, NY 10504-2219 · (718) 570-5063
Phone(203) 869-1285
Fax(203) 737-8035
Sole ProprietorNo
Enumeration DateMay 22, 2010
Last NPPES UpdateSeptember 12, 2019
✔ NPI 1770802357 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyUrologyAllopathic & Osteopathic Physicians
Taxonomy Code208800000X
Licenses✔ Licensed in CT · 49084✔ Licensed in NY · 241260
Definition
A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has comprehensive knowledge of and skills in endoscopic, percutaneous and open surgery of congenital and acquired conditions of the urinary and reproductive systems and their contiguous structures.
49 LAKE AVE, Greenwich, CT 06830
Open in Google Maps ↗

Other Names 1

Former Name (1)Catherine Lea Michels M.d.

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Catherine Michels Alonzo 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.

Medicare Billing Reassignment

Medicare enrollment records show Catherine Alonzo reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Yale University
41 mi
Advanced Practice Midwife
100 CHURCH ST S STE 200, YALE SCHOOL OF NURSING
New Haven, CT 06519
  • Reassigned Medicare billing, Connecticut enrollment
  • 3,728 clinicians in this Medicare group
NPI 1124148887 (203) 737-5432

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 06830 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
$75.55 typical visit price
range $19.76 – $149.26
Typical copayment $18.88 (range $4.94 – $37.31)
Most-billed visit code 99213
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

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Intermittent urinary catheter; straight tip, with or without coating (teflon, silicone, silicone elastomer, or hydrophilic, etc.), each A4351
DME-Orthotic Devices · category DF008N
4 suppliers41 claims5,520 services$1.58 avg. paid by Medicare
Intermittent urinary catheter; coude (curved) tip, with or without coating (teflon, silicone, silicone elastomeric, or hydrophilic, etc.), each A4352
DME-Orthotic Devices · category DF008N
2 suppliers12 claims1,560 services$5.19 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

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.

DR. DAVID D EVANS M.D.
Radiology (Diagnostic Radiology)
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 861-2381
DR. JAMES STEPHEN BORGES MD
Specialist
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 661-2934
CENTER FOR ORAL AND IMPLANT SURGERY OF GREENWICH, LLC
Clinic/Center (Oral and Maxillofacial Surgery)
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 661-4231
DR. LYNNE M HAVEN M. D.,
Dermatology
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 869-4242
DR. MICHELE SHOSHANA BERGEN D.M.D., M.D.
Dentist (Oral and Maxillofacial Surgery)
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 661-4231
VINOD RAVIKUMAR M.D. LLC
Clinic/Center (Health Service)
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (845) 368-8808
JOSHUA JABLONSKI
Audiologist
49 LAKE AVE, SUITE 103
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 869-2030
MR. LOUIS VISCONTI
Pharmacist
49 LAKE AVE
GREENWICH, CT 06830
Western Connecticut Planning Region (203) 869-5700

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 Catherine Alonzo's NPI number?

The NPI number for Catherine Alonzo is 1770802357. It was assigned to this individual provider in the NPPES registry on May 22, 2010. The provider is also known as Catherine Lea Michels M.D..

Where is Catherine Alonzo located?

Catherine Alonzo practices at 49 Lake Ave Suite 201, Greenwich, CT 06830. The listed phone number is (203) 869-1285.

What is Catherine Alonzo's specialty?

The primary specialty registered for this NPI is Urology with taxonomy code 208800000X.

Is Catherine Alonzo enrolled in Medicare?

Yes. Catherine Alonzo is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Catherine Alonzo's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Catherine Alonzo reassigns Medicare benefits to Yale University (New Haven, CT). 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 Catherine Alonzo'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 Catherine Alonzo was last updated on September 12, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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.