DR. JOHN JOSEPH MCGRATH III MD
NPI 1215913157
Radiology - Radiation Oncology in Concord, MA
About Dr. John Joseph Mcgrath Iii Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. JOHN JOSEPH MCGRATH III MD (NPI 1215913157) is an individual radiation oncology provider in Concord, Massachusetts, licensed in Massachusetts (157106) and active in the NPI registry since December 2005. He is enrolled in Medicare PECOS, is affiliated with Massachusetts General Hospital, and is a graduate of University Of Vermont College Of Medicine (1993).
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 3
Accepted Insurance
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. John Joseph Mcgrath Iii Md 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 John Mcgrath reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,360 clinicians in this Medicare group
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,234 clinicians in this Medicare group
Northampton, MA 01060
- Reassigned Medicare billing, Massachusetts enrollment
- 539 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.
Areas of Expertise CMS Part B claims 16
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare 5
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Massachusetts General Hospital
Acute Care Hospitals · Boston, MAMassachusetts Eye And Ear Infirmary -
Acute Care Hospitals · Boston, MAEmerson Hospital -
Acute Care Hospitals · W Concord, MANewton-Wellesley Hospital
Acute Care Hospitals · Newton, MALahey Hospital & Medical Center, Burlington
Acute Care Hospitals · Burlington, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 01742 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
CONCORD, MA 01742
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 John Mcgrath's NPI number?
The NPI number for John Mcgrath is 1215913157. It was assigned to this individual provider in the NPPES registry on December 22, 2005.
Where is John Mcgrath located?
John Mcgrath practices at Old Road To Nine Acre Corner Emerson Hospital Radiation Medicine, Concord, MA 01742. The listed phone number is (978) 287-3290.
What is John Mcgrath's specialty?
The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.
Is John Mcgrath enrolled in Medicare?
Yes. John Mcgrath 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 John Mcgrath's services?
According to the CMS Revalidation Reassignment List (October 2026 release), John Mcgrath reassigns Medicare benefits to 3 organizations: Massachusetts General Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA) and Mass General Brigham Medical Group Western Massachusetts Inc (Northampton, 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 John Mcgrath's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does John Mcgrath accept?
Health plans from Anthem Blue Cross and Blue Shield and Taro Health list John Mcgrath as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is John Mcgrath affiliated with any hospitals?
According to CMS data, John Mcgrath is affiliated with Massachusetts General Hospital, Massachusetts Eye And Ear Infirmary -, Emerson Hospital -, Newton-Wellesley Hospital and Lahey Hospital & Medical Center, Burlington.
When was this NPI record last updated?
The NPPES record for John Mcgrath was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.
# Dr. John Joseph Mcgrath III, MD · NPI 1215913157
Radiation Oncology physician in Concord, Massachusetts. Individual provider, active in the CMS NPPES registry since December 22, 2005.
## Identity
- **NPI:** 1215913157 (Entity type: Individual)
- **Enumerated:** December 22, 2005
- **Primary specialty:** Radiology - Radiation Oncology · taxonomy 2085R0001X
- **State license:** 157106 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** OLD ROAD TO NINE ACRE CORNER, EMERSON HOSPITAL RADIATION MEDICINE, Concord, MA 01742
- **Phone:** (978) 287-3290 · **Fax:** (978) 287-3295
## 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): Massachusetts General Physicians Organization Inc (NPI 1801874573, Boston, MA); The General Hospital Corporation (NPI 1023049236, Boston, MA); Mass General Brigham Medical Group Western Massachusetts Inc (NPI 1295787919, Northampton, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Vermont College Of Medicine, class of 1993
## Record status
- **NPPES last updated:** July 13, 2026
- **Other identifiers:** Medicaid 3179508 (MA); Other 791236 (MA); Other J18882 (MA)
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Source: [NPI Profile](https://npiprofile.com/npi/1215913157) · Data from the CMS NPPES public registry.