GRIER H MERWIN M.D.
NPI 1255378204
Family Medicine in Dorchester, MA
About Grier H Merwin M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
GRIER H MERWIN M.D. (NPI 1255378204) is an individual family medicine provider in Dorchester, Massachusetts, licensed in Massachusetts (35314) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS and is a graduate of Columbia University College Of Physicians And Surgeons (1967).
NPPES Registry Identity
Specialties & Licenses
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
Grier H Merwin M.d. 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 Reassignment
Medicare enrollment records show Grier Merwin reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Dorchester, MA 02125
- Reassigned Medicare billing, Massachusetts enrollment
- Medicare enrollment name: Uphams Corner Health Committee Inc
- 55 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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 02125 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 2
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
DORCHESTER, MA 02125
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 Grier Merwin's NPI number?
The NPI number for Grier Merwin is 1255378204. It was assigned to this individual provider in the NPPES registry on May 31, 2006.
Where is Grier Merwin located?
Grier Merwin practices at 500 Columbia Road Upham's Corner Health Ctr, Dorchester, MA 02125. The listed phone number is (617) 287-8000.
What is Grier Merwin's specialty?
The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.
Is Grier Merwin enrolled in Medicare?
Yes. Grier Merwin 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 organization bills Medicare for Grier Merwin's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Grier Merwin reassigns Medicare benefits to Upham's Corner Health Committee, Inc. (Dorchester, MA). The 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 Grier Merwin's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Grier Merwin accept?
Health plans from Anthem Blue Cross and Blue Shield list Grier Merwin 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.
When was this NPI record last updated?
The NPPES record for Grier Merwin was last updated on March 22, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years 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.
# Grier H Merwin, M.D. · NPI 1255378204
Family Medicine physician in Dorchester, Massachusetts. Individual provider, active in the CMS NPPES registry since May 31, 2006.
## Identity
- **NPI:** 1255378204 (Entity type: Individual)
- **Enumerated:** May 31, 2006
- **Primary specialty:** Family Medicine · taxonomy 207Q00000X
- **State license:** 35314 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 500 COLUMBIA ROAD, UPHAM'S CORNER HEALTH CTR, Dorchester, MA 02125
- **Phone:** (617) 287-8000
## 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:** Upham's Corner Health Committee, Inc. (NPI 1780780486, Dorchester, MA), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Columbia University College Of Physicians And Surgeons, class of 1967
## Record status
- **NPPES last updated:** March 22, 2018
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Source: [NPI Profile](https://npiprofile.com/npi/1255378204) · Data from the CMS NPPES public registry.