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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

GRACE K. MAHOWALD MD, PHD
NPI 1659665685
Pathology - Clinical Pathology in Boston, MA

Active since June 07, 2011
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET, BOSTON, MA 02114(617) 726-2865 Get Directions Write a Review

NPPES record last updated: July 21, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Jul 21, 2026, Oct 17, 2019 (2 updates tracked since 2019).

About Grace K. Mahowald Md, Phd NPPES

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

GRACE K. MAHOWALD MD, PHD (NPI 1659665685) is an individual clinical pathology provider in Boston, Massachusetts, licensed in Massachusetts (L-247754) and active in the NPI registry since June 2011. She maintains a secondary practice location in Boston.

NPPES Registry Identity

NPI1659665685
Entity TypeIndividualFemale
Primary Taxonomy207ZC0006X
Provider Legal NameGRACE K. MAHOWALDCredential: MD, PHD
Location AddressMASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREETBoston, MA 02114
Mailing AddressMassachusetts General Hospital, 55 Fruit StreetBoston, MA 02114 · (617) 724-3767
Phone(617) 726-2865
Sole ProprietorNo
Enumeration DateJune 7, 2011
Last NPPES UpdateJuly 21, 20262 updates tracked since enumeration
NPPES CertifiedJuly 21, 2026
✔ NPI 1659665685 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPathology · Clinical PathologyAllopathic & Osteopathic Physicians
Taxonomy Code207ZC0006X
License✔ Licensed in MA · L-247754
Definition
A pathologist deals with the causes and nature of disease and contributes to diagnosis, prognosis and treatment through knowledge gained by the laboratory application of the biologic, chemical and physical sciences. A pathologist uses information gathered from the microscopic examination of tissue specimens, cells and body fluids, and from clinical laboratory tests on body fluids and secretions for the diagnosis, exclusion and monitoring of disease.
MASSACHUSETTS GENERAL HOSPITAL, Boston, MA 02114
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Secondary Practice Location 1

Location 175 Francis StBoston, MA 02115-6110 · Phone (617) 724-3767

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.

KAITLYN MY-TU LAM MBBS
Internal Medicine (Cardiovascular Disease)
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET
BOSTON, MA 02114
Suffolk County (617) 724-7738
ALAKA RAY M.D.
Internal Medicine
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET
BOSTON, MA 02114
Suffolk County (617) 726-2066
MEGHAN E SISE M.D.
Internal Medicine (Nephrology)
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET
BOSTON, MA 02114
Suffolk County (617) 726-2862
HUGH G AUCHINCLOSS M.D.
Thoracic Surgery (Cardiothoracic Vascular Surgery)
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET
BOSTON, MA 02114
Suffolk County (617) 726-2000
ANGELA M. JACQUES MD
Pediatrics
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT ST.
BOSTON, MA 02114
Suffolk County (617) 726-2066
NICOLE J LOOK-HONG MD, MSC
Surgery (Surgical Oncology)
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT ST.
BOSTON, MA 02114
Suffolk County (617) 724-3868
CORINNA M ELLIOTT MA
Student in an Organized Health Care Education/Training Program
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT STREET
BOSTON, MA 02114
Suffolk County (617) 724-5600
KIRAN J AGARWAL-HARDING MD
Orthopaedic Surgery
MASSACHUSETTS GENERAL HOSPITAL, 55 FRUIT ST.
BOSTON, MA 02114
Suffolk County (617) 726-2942

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 Grace Mahowald's NPI number?

The NPI number for Grace Mahowald is 1659665685. It was assigned to this individual provider in the NPPES registry on June 7, 2011.

Where is Grace Mahowald located?

Grace Mahowald practices at Massachusetts General Hospital 55 Fruit Street, Boston, MA 02114. The listed phone number is (617) 726-2865.

What is Grace Mahowald's specialty?

The primary specialty registered for this NPI is Pathology, specializing in Clinical Pathology, with taxonomy code 207ZC0006X.

When was this NPI record last updated?

The NPPES record for Grace Mahowald was last updated on July 21, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 20 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.