NPI Portal NPI Lookup & Verification

John G Grantham, M.D.

John G Grantham is a Diagnostic Radiology Physician provider (Radiology) practicing in Boulder, CO, registered in the NPPES registry with NPI 1992789614 since 2005. The credential MD stands for Doctor of Medicine.

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NPI 1992789614
Entity type Individual (Type 1)
Name John G Grantham
Credential M.D.
Sex Male
Practice address 2750 BROADWAY ST, Boulder, CO, 80304
Phone 3034403000
Enumeration date 2005-12-06
Last updated in NPPES 2012-10-31

Taxonomy & licenses

Taxonomy code Specialty Primary License State
2085R0202X Diagnostic Radiology Physician Primary 26497 CO

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Copy-ready billing details
Provider: John Grantham, M.D.
NPI: 1992789614
Taxonomy: 2085R0202X (Diagnostic Radiology Physician)
Address: 2750 BROADWAY ST, Boulder, CO, 80304

Other providers at this practice address

NPI Name Type Specialty Location
1275537078 Emma Mccarty Individual Internal Medicine Physician Boulder, CO
1457358228 Lee Brennan Individual Physical Therapist Boulder, CO
1205836889 Larry Munch Individual Urology Physician Boulder, CO
1316948797 Barry Migicovsky Individual Gastroenterology Physician Boulder, CO
1821082819 Paula Mendes Individual Neurology Physician Boulder, CO
1750365565 Karen Andrews Individual Allergy Physician Boulder, CO
1750365417 Jennifer Christensen Individual Internal Medicine Physician Boulder, CO
1356325013 Coco Dughi Individual Internal Medicine Physician Boulder, CO

Verify this record

Cross-check NPI 1992789614 against the authoritative CMS record: view John G Grantham on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

What specialty is John Grantham?
John Grantham is registered in NPPES with the primary taxonomy of Diagnostic Radiology Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2012-10-31.