DR. RYAN J SULLIVAN MD
NPI 1881696003
Internal Medicine in Cambridge, MA
About Dr. Ryan J Sullivan Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. RYAN J SULLIVAN MD (NPI 1881696003) is an individual internal medicine provider in Cambridge, Massachusetts, licensed in Massachusetts (222743) and active in the NPI registry since June 2005. He is enrolled in Medicare PECOS, is affiliated with Massachusetts General Hospital, and is a graduate of University Of Connecticut School Of Medicine (2001).
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. Ryan J Sullivan 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
4Medicare enrollment records show Ryan Sullivan reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 4,574 clinicians in this Medicare group
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
Newton, MA 02462
- Reassigned Medicare billing, Massachusetts enrollment
- 992 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 7
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, MANewton-Wellesley Hospital
Acute Care Hospitals · Newton, MABrigham And Women's Hospital
Acute Care Hospitals · Boston, MANantucket Cottage Hospital
Acute Care Hospitals · Nantucket, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 02138 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 7
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
CAMBRIDGE, MA 02138
CAMBRIDGE, MA 02138
CAMBRIDGE, MA 02138
CAMBRIDGE, MA 02138
CAMBRIDGE, MA 02138
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 Ryan Sullivan's NPI number?
The NPI number for Ryan Sullivan is 1881696003. It was assigned to this individual provider in the NPPES registry on June 1, 2005.
Where is Ryan Sullivan located?
Ryan Sullivan practices at 330 Mt Auburn St, Cambridge, MA 02138. The listed phone number is (617) 499-5112.
What is Ryan Sullivan's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Ryan Sullivan enrolled in Medicare?
Yes. Ryan Sullivan 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 Ryan Sullivan's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Ryan Sullivan reassigns Medicare benefits to 4 organizations: Brigham & Womens Physicians Organization Inc (Boston, MA), Massachusetts General Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA) and Mass General Brigham Medical Group Suburban Massachusetts Inc (Newton, 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 Ryan Sullivan's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Ryan Sullivan accept?
Health plans from Taro Health list Ryan Sullivan 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 Ryan Sullivan affiliated with any hospitals?
According to CMS data, Ryan Sullivan is affiliated with Massachusetts General Hospital, Massachusetts Eye And Ear Infirmary -, Newton-Wellesley Hospital, Brigham And Women's Hospital and Nantucket Cottage Hospital.
When was this NPI record last updated?
The NPPES record for Ryan Sullivan was last updated on March 24, 2009. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 17 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. Ryan J Sullivan, MD · NPI 1881696003
Internal Medicine physician in Cambridge, Massachusetts. Individual provider, active in the CMS NPPES registry since June 1, 2005.
## Identity
- **NPI:** 1881696003 (Entity type: Individual)
- **Enumerated:** June 1, 2005
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** 222743 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 330 MT AUBURN ST, Cambridge, MA 02138-5502
- **Phone:** (617) 499-5112 · **Fax:** (617) 575-8608
## 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:** 4 organizations under Medicare reassignment (form CMS-855R): Brigham & Womens Physicians Organization Inc (NPI 1033535497, Boston, MA); Massachusetts General Physicians Organization Inc (NPI 1801874573, Boston, MA); The General Hospital Corporation (NPI 1023049236, Boston, MA); Mass General Brigham Medical Group Suburban Massachusetts Inc (NPI 1538191218, Newton, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Connecticut School Of Medicine, class of 2001
## Record status
- **NPPES last updated:** March 24, 2009
- **Other identifiers:** Medicaid 2097702 (MA); Medicare UPIN I24820 (MA); Medicare ID-Type Unspecified A38111 (MA)
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Source: [NPI Profile](https://npiprofile.com/npi/1881696003) · Data from the CMS NPPES public registry.