Gregory Fenton, M.D.
Internal Medicine Physician · Boston, MA
Gregory Fenton, M.D. is an internal medicine physician with a practice address in Boston, Massachusetts, and NPI 1841272846, issued on Nov 16, 2005. Check the license (Massachusetts 79666, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Gregory Fenton
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 79666 MA
Self-reported in NPPES; status is on the state search - Practice location
- 75 Kneeland St, Boston, MA 02111
- Phone
- (617) 457-8140
- Enumerated
- Nov 16, 2005
- Record last updated
- Jul 8, 2013 (not updated in 13 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20060510000464); accepts Medicare assignment
- Medical or professional school
- R Franklin University Of Med & Sci/Chicago Medical School, 1992
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 6,825 in Massachusetts → Look up another NPI →
Also registered at 75 Kneeland St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Sean Borger, LCSWClinical Social Worker1457996563
- Karla Hoxha Brown, N.P.Community Health Nurse Practitioner1295046076
- Rachel Kahn, LMHCMental Health Counselor1497012405
- Katherine Luciano, LICSWClinical Social Worker1811479900
- Jay Luthar, M.D.Internal Medicine Physician1124552567
- Wayne Pearson, LICSWClinical Social Worker1811531965
Verify Gregory Fenton in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 79666Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
98% fewer Medicare Part D claims than the average internal medicine physician in 2024
73 Medicare Part D claims for 34 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 18% of claims.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Bills Medicare through one group practice
- Fenway Community Health Center, IncBoston, MA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Gregory Fenton among 6,825 internal medicine physician records in Massachusetts
Gregory Fenton, M.D. is one of 6,825 internal medicine physician records with a practice address in Massachusetts. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 88% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 60% of these records are
- Graduated1992 · median 2004 among the 4,103 with a school on file
- Record last updated2013 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
2,320 internal medicine physician records list a practice address in Boston
They are 2,320 of the 41,865 NPPES records with a practice address in Boston, and 6,825 internal medicine physician records in Massachusetts.
All 6,825 in Massachusetts → Every provider in Boston → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Dineli Ahearn, M.D.Boston, MA 021111528015922
- Ethan Balk, M.D.Boston, MA 021111831136571
- Jeanine Carlson, M.D.Boston, MA 021111588603013
- Peter Castaldi, M.D.Boston, MA 021111902891062
- Daniel Chandler, M.D.Boston, MA 021111760440168
- Wambui Chege, M.D.Boston, MA 021111275571549
- Kevin Chin, MDBoston, MA 021111568430593
- Shira Doron, M.D.Boston, MA 021111831121359
Common questions
What is Gregory Fenton, M.D.'s NPI number?
Gregory Fenton, M.D.'s National Provider Identifier (NPI) is 1841272846, issued on Nov 16, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Gregory Fenton, M.D. located?
The NPPES record lists a practice address at 75 Kneeland St, Boston, MA, 02111. Phone: (617) 457-8140. Providers update this record themselves, so call before visiting.
How can I verify Gregory Fenton, M.D.'s license?
NPPES lists Massachusetts license number 79666, as entered by the provider. Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Gregory Fenton, M.D. prescribe under Medicare Part D?
In 2024, Gregory Fenton, M.D. had 73 Medicare Part D claims for 34 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.