DR. MARIEL H SMITH MD
NPI 1659637841
Pediatrics - Pediatric Hematology-Oncology in Boston, MA
About Dr. Mariel H Smith Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. MARIEL H SMITH MD (NPI 1659637841) is an individual pediatric hematology-oncology provider in Boston, Massachusetts, licensed in Massachusetts (281236) and active in the NPI registry since April 2012. She is enrolled in Medicare PECOS and maintains a secondary practice location in New York.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Location 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Dr. Mariel H Smith Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Mariel Smith reassigns Medicare billing to 2 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
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BOSTON, MA 02114
BOSTON, MA 02114
BOSTON, MA 02114
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 Mariel Smith's NPI number?
The NPI number for Mariel Smith is 1659637841. It was assigned to this individual provider in the NPPES registry on April 2, 2012.
Where is Mariel Smith located?
Mariel Smith practices at 55 Fruit St, Boston, MA 02114. The listed phone number is (617) 726-2737.
What is Mariel Smith's specialty?
The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Hematology-Oncology, with taxonomy code 2080P0207X.
Is Mariel Smith enrolled in Medicare?
Yes. Mariel Smith is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Mariel Smith's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mariel Smith reassigns Medicare benefits to 2 organizations: Massachusetts General Physicians Organization Inc (Boston, MA) and The General Hospital Corporation (Boston, 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 Mariel Smith's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Mariel Smith was last updated on August 15, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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.
# Dr. Mariel H Smith, MD · NPI 1659637841
Pediatric Hematology-Oncology physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since April 2, 2012.
## Identity
- **NPI:** 1659637841 (Entity type: Individual)
- **Enumerated:** April 2, 2012
- **Primary specialty:** Pediatrics - Pediatric Hematology-Oncology · taxonomy 2080P0207X
- **State license:** 281236 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 55 FRUIT ST, Boston, MA 02114-2621
- **Phone:** (617) 726-2737
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Massachusetts General Physicians Organization Inc (NPI 1801874573, Boston, MA); The General Hospital Corporation (NPI 1023049236, Boston, MA) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** August 15, 2019
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Source: [NPI Profile](https://npiprofile.com/npi/1659637841) · Data from the CMS NPPES public registry.