WILLIAM DEMARCO DO
NPI 1124103577
Internal Medicine in Great Barrington, MA
About William Demarco Do NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WILLIAM DEMARCO DO (NPI 1124103577) is an individual internal medicine provider in Great Barrington, Massachusetts, licensed in Massachusetts (59492) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS, is affiliated with Berkshire Medical Center, and is a graduate of University Of New England, College Of Osteo Medicine (1984).
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 3
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
William Demarco Do 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.
Medicare Billing Reassignments
2Medicare enrollment records show William Demarco reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Pittsfield, MA 01201
- Reassigned Medicare billing, Massachusetts enrollment
- 394 clinicians in this Medicare group
North Adams, MA 01247
- Reassigned Medicare billing, Massachusetts enrollment
- Also billed through NPI 1437839669 (Massachusetts)
- 153 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Berkshire Medical Center
Acute Care Hospitals · Pittsfield, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 01230 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
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.
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 Demarco's NPI number?
The NPI number for William Demarco is 1124103577. It was assigned to this individual provider in the NPPES registry on October 26, 2006.
Where is William Demarco located?
William Demarco practices at 29 Lewis Ave, Great Barrington, MA 01230. The listed phone number is (413) 496-6820.
What is William Demarco's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is William Demarco enrolled in Medicare?
Yes. William Demarco 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.
Which organizations bill Medicare for William Demarco's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Demarco reassigns Medicare benefits to 2 organizations: Berkshire Medical Center, Inc (Pittsfield, MA) and North Adams Regional Hospital Corporation (North Adams, MA). Each 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 Demarco's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
Is William Demarco affiliated with any hospitals?
According to CMS data, William Demarco is affiliated with Berkshire Medical Center.
When was this NPI record last updated?
The NPPES record for William Demarco was last updated on January 24, 2008. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 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.
# William Demarco, DO · NPI 1124103577
Internal Medicine physician in Great Barrington, Massachusetts. Individual provider, active in the CMS NPPES registry since October 26, 2006.
## Identity
- **NPI:** 1124103577 (Entity type: Individual)
- **Enumerated:** October 26, 2006
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** 59492 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 29 LEWIS AVE, Great Barrington, MA 01230
- **Phone:** (413) 496-6820 · **Fax:** (413) 496-6821
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Berkshire Medical Center, Inc (NPI 1295765261, Pittsfield, MA); North Adams Regional Hospital Corporation (NPI 1316727761, North Adams, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of New England, College Of Osteo Medicine, class of 1984
## Record status
- **NPPES last updated:** January 24, 2008
- **Other identifiers:** Medicare UPIN E34190; Medicaid 3045161 (MA); Medicare ID-Type Unspecified J08055 (MA)
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Source: [NPI Profile](https://npiprofile.com/npi/1124103577) · Data from the CMS NPPES public registry.