DR. MARK D FLEMING MD
NPI 1235148404
Pathology - Hematology in Boston, MA
About Dr. Mark D Fleming Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. MARK D FLEMING MD (NPI 1235148404) is an individual hematology provider in Boston, Massachusetts, licensed in Massachusetts (153834) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS and is a graduate of Harvard Medical School (1993).
NPPES Registry Identity
Specialties & Licenses 2
Other Identifiers 1
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. Mark D Fleming 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 Reassignment
Medicare enrollment records show Mark Fleming reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 35 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 02115 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 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
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 Mark Fleming's NPI number?
The NPI number for Mark Fleming is 1235148404. It was assigned to this individual provider in the NPPES registry on August 6, 2006.
Where is Mark Fleming located?
Mark Fleming practices at 300 Longwood Ave, Boston, MA 02115. The listed phone number is (617) 919-2664.
What is Mark Fleming's specialty?
The primary specialty registered for this NPI is Pathology, specializing in Hematology, with taxonomy code 207ZH0000X.
Is Mark Fleming enrolled in Medicare?
Yes. Mark Fleming 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 Mark Fleming's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mark Fleming reassigns Medicare benefits to Children's Hospital Pathology Foundation, Inc. (Boston, 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 Mark Fleming's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Mark Fleming accept?
Health plans from Taro Health list Mark Fleming 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 Mark Fleming was last updated on August 20, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 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. Mark D Fleming, MD · NPI 1235148404
Hematology physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since August 6, 2006.
## Identity
- **NPI:** 1235148404 (Entity type: Individual)
- **Enumerated:** August 6, 2006
- **Primary specialty:** Pathology - Hematology · taxonomy 207ZH0000X
- **State license:** 153834 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 300 LONGWOOD AVE, Boston, MA 02115-5724
- **Phone:** (617) 919-2664 · **Fax:** (617) 730-0168
## 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:** Children's Hospital Pathology Foundation, Inc. (NPI 1376502112, Boston, MA), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Harvard Medical School, class of 1993
## Record status
- **NPPES last updated:** August 20, 2007
- **Other identifiers:** Medicare UPIN G55389
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Source: [NPI Profile](https://npiprofile.com/npi/1235148404) · Data from the CMS NPPES public registry.