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DR. WILLIAM CHRISTOPHER BROWN M.D.
NPI 1679519979
Specialist in Old Greenwich, CT

Active since June 22, 2006PECOS Enrolled
1385 E PUTNAM AVE, OLD GREENWICH, CT 06870(203) 863-1180(203) 863-1182 Get Directions Write a Review

NPPES record last updated: April 27, 2017. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Dr. William Christopher Brown M.d. NPPES

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

DR. WILLIAM CHRISTOPHER BROWN M.D. (NPI 1679519979) is an individual specialist in Old Greenwich, Connecticut, licensed in Connecticut (31641) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1679519979
Entity TypeIndividualMale
Primary Taxonomy174400000X
Provider Legal NameDR. WILLIAM CHRISTOPHER BROWNCredential: M.D.
Location Address1385 E PUTNAM AVEOld Greenwich, CT 06870-1305
Mailing Address1385 E Putnam AveOld Greenwich, CT 06870-1305 · (203) 863-1180 · Fax (203) 863-1182
Phone(203) 863-1180
Fax(203) 863-1182
Sole ProprietorNo
Enumeration DateJune 22, 2006
Last NPPES UpdateApril 27, 2017
✔ NPI 1679519979 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySpecialistOther Service Providers
Taxonomy Code174400000X
License✔ Licensed in CT · 31641
Definition
An individual educated and trained in an applied knowledge discipline used in the performance of work at a level requiring knowledge and skills beyond or apart from that provided by a general education or liberal arts degree.
1385 E PUTNAM AVE, Old Greenwich, CT 06870
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Other Identifiers 2

Medicare PIN340000351
Medicare UPIND79762CT

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. William Christopher Brown 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 William Brown reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Greenwich Hospital
3.0 mi
General Acute Care Hospital
5 PERRYRIDGE RD
Greenwich, CT 06830
  • Reassigned Medicare billing, Connecticut enrollment
  • 268 clinicians in this Medicare group
NPI 1609846088 (203) 863-3000

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

Other Providers at the Same Location NPPES 2

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

EILEEN LI PT, DPT, L.AC
Acupuncturist
1385 E PUTNAM AVE
OLD GREENWICH, CT 06870
Western Connecticut Planning Region (203) 900-4279
THE UROLOGY CLINIC OF GREENWICH PC
Urology
1385 E PUTNAM AVE
OLD GREENWICH, CT 06870
Western Connecticut Planning Region (203) 863-1180

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 William Brown's NPI number?

The NPI number for William Brown is 1679519979. It was assigned to this individual provider in the NPPES registry on June 22, 2006.

Where is William Brown located?

William Brown practices at 1385 E Putnam Ave, Old Greenwich, CT 06870. The listed phone number is (203) 863-1180.

What is William Brown's specialty?

The primary specialty registered for this NPI is Specialist with taxonomy code 174400000X.

Is William Brown enrolled in Medicare?

Yes. William Brown is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for William Brown's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Brown reassigns Medicare benefits to Greenwich Hospital (Greenwich, 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 William Brown'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 William Brown was last updated on April 27, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 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.