DR. MARGARET M. FABISZAK MD, PHD
NPI 1487399028
Anesthesiology in Boston, MA
About Dr. Margaret M. Fabiszak Md, Phd NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. MARGARET M. FABISZAK MD, PHD (NPI 1487399028) is an individual anesthesiology provider in Boston, Massachusetts, licensed in Massachusetts (3013831) and active in the NPI registry since April 2022. She is enrolled in Medicare PECOS, is affiliated with Brigham And Women's Hospital, and maintains a secondary practice location in Boston.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
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
Dr. Margaret M. Fabiszak Md, Phd 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
3Medicare enrollment records show Margaret Fabiszak reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 4,574 clinicians in this Medicare group
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,234 clinicians in this Medicare group
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,360 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.
Brigham And Women's Hospital
Acute Care Hospitals · Boston, MAOther Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
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 Margaret Fabiszak's NPI number?
The NPI number for Margaret Fabiszak is 1487399028. It was assigned to this individual provider in the NPPES registry on April 28, 2022.
Where is Margaret Fabiszak located?
Margaret Fabiszak practices at 75 Francis St, Boston, MA 02115. The listed phone number is (617) 732-8210.
What is Margaret Fabiszak's specialty?
The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.
Is Margaret Fabiszak enrolled in Medicare?
Yes. Margaret Fabiszak 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 Margaret Fabiszak's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Margaret Fabiszak reassigns Medicare benefits to 3 organizations: Brigham & Womens Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA) and Massachusetts General Physicians Organization Inc (Boston, 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 Margaret Fabiszak's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
Is Margaret Fabiszak affiliated with any hospitals?
According to CMS data, Margaret Fabiszak is affiliated with Brigham And Women's Hospital.
When was this NPI record last updated?
The NPPES record for Margaret Fabiszak was last updated on August 26, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 57 days 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.
# Dr. Margaret M. Fabiszak, MD, PHD · NPI 1487399028
Anesthesiology physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since April 28, 2022.
## Identity
- **NPI:** 1487399028 (Entity type: Individual)
- **Enumerated:** April 28, 2022
- **Primary specialty:** Anesthesiology · taxonomy 207L00000X
- **State license:** 3013831 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 75 FRANCIS ST, Boston, MA 02115-6110
- **Phone:** (617) 732-8210
## 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:** 3 organizations under Medicare reassignment (form CMS-855R): Brigham & Womens Physicians Organization Inc (NPI 1033535497, Boston, MA); The General Hospital Corporation (NPI 1023049236, Boston, MA); Massachusetts General Physicians Organization Inc (NPI 1801874573, Boston, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2022
## Record status
- **NPPES last updated:** August 26, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1487399028) · Data from the CMS NPPES public registry.