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ALDEN G GAGNON M.D.
NPI 1912966011
Internal Medicine - Hematology in Chelmsford, MA

Active since March 20, 2006
23 VILLAGE SQ, CHELMSFORD, MA 01824(978) 256-4121(978) 250-3210 Get Directions Write a Review

NPPES record last updated: September 11, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Alden G Gagnon M.d. NPPES

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

ALDEN G GAGNON M.D. (NPI 1912966011) is an individual hematology provider in Chelmsford, Massachusetts, licensed in Massachusetts (29255) and active in the NPI registry since March 2006.

NPPES Registry Identity

NPI1912966011
Entity TypeIndividualMale
Primary Taxonomy207RH0000X
Provider Legal NameALDEN G GAGNONCredential: M.D.
Location Address23 VILLAGE SQChelmsford, MA 01824-2712
Mailing AddressPo Box 1807Merrimack, NH 03054-1807 · (603) 673-9411 · Fax (603) 673-9899
Phone(978) 256-4121
Fax(978) 250-3210
Sole ProprietorYes
Enumeration DateMarch 20, 2006
Last NPPES UpdateSeptember 11, 2025
✔ NPI 1912966011 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · HematologyAllopathic & Osteopathic Physicians
Taxonomy Code207RH0000X
License✔ Licensed in MA · 29255
Definition
An internist with additional training who specializes in diseases of the blood, spleen and lymph. This specialist treats conditions such as anemia, clotting disorders, sickle cell disease, hemophilia, leukemia and lymphoma.
Also ListedInternal MedicineTaxonomy 207R00000X · License 29255 (MA)

Other Identifiers 9

Other709837MA · Tufts Health Plan
Other99390801MA · Network Health
Other60521NH · Healthsource
Other20696MA · Fallon Comm Health Plan
OtherB13017MA · Bcbs
Medicaid30006380NH
Medicaid0130249MA
Other3000077MA · United Healthcare
Other64833MA · Harvard Pilgrim

Other Providers at the Same Location NPPES 3

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

DEIRDRE M CONNOLLY MD
Family Medicine
23 VILLAGE SQ
CHELMSFORD, MA 01824
Middlesex County (978) 323-2835
HOLLY POWDERLY NP
Nurse Practitioner
23 VILLAGE SQ
CHELMSFORD, MA 01824
Middlesex County (978) 323-2835
SPYRIDON KANTAS MD PC
Internal Medicine
23 VILLAGE SQ
CHELMSFORD, MA 01824
Middlesex County (978) 256-4121

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 Alden Gagnon's NPI number?

The NPI number for Alden Gagnon is 1912966011. It was assigned to this individual provider in the NPPES registry on March 20, 2006.

Where is Alden Gagnon located?

Alden Gagnon practices at 23 Village Sq, Chelmsford, MA 01824. The listed phone number is (978) 256-4121.

What is Alden Gagnon's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology, with taxonomy code 207RH0000X.

When was this NPI record last updated?

The NPPES record for Alden Gagnon was last updated on September 11, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 months 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.