MRS. CAROL MICHELLE ILZARBE M.D.
NPI 1124253828
Pediatrics in Cambridge, MA
About Mrs. Carol Michelle Ilzarbe M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MRS. CAROL MICHELLE ILZARBE M.D. (NPI 1124253828) is an individual pediatrics provider in Cambridge, Massachusetts, licensed in Massachusetts (251823) and active in the NPI registry since May 2009. She is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Mrs. Carol Michelle Ilzarbe M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
4Medicare enrollment records show Carol Ilzarbe reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Cambridge, MA 02138
- Reassigned Medicare billing, Massachusetts enrollment
- 423 clinicians in this Medicare group
Cambridge, MA 02139
- Reassigned Medicare billing, Massachusetts enrollment
- 719 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
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 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 20
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
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 Carol Ilzarbe's NPI number?
The NPI number for Carol Ilzarbe is 1124253828. It was assigned to this individual provider in the NPPES registry on May 25, 2009.
Where is Carol Ilzarbe located?
Carol Ilzarbe practices at 330 Mount Auburn St, Cambridge, MA 02138. The listed phone number is (860) 545-9970.
What is Carol Ilzarbe's specialty?
The primary specialty registered for this NPI is Pediatrics with taxonomy code 208000000X.
Is Carol Ilzarbe enrolled in Medicare?
Yes. Carol Ilzarbe is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Carol Ilzarbe's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Carol Ilzarbe reassigns Medicare benefits to 4 organizations: Mount Auburn Professional Services Inc (Cambridge, MA), Cambridge Public Health Commission (Cambridge, MA), 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 Carol Ilzarbe'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 Carol Ilzarbe was last updated on August 27, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.
# Mrs. Carol Michelle Ilzarbe, M.D. · NPI 1124253828
Pediatrics physician in Cambridge, Massachusetts. Individual provider, active in the CMS NPPES registry since May 25, 2009.
## Identity
- **NPI:** 1124253828 (Entity type: Individual)
- **Enumerated:** May 25, 2009
- **Primary specialty:** Pediatrics · taxonomy 208000000X
- **State license:** 251823 (Massachusetts)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 330 MOUNT AUBURN ST, Cambridge, MA 02138-5502
- **Phone:** (860) 545-9970
## 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:** 4 organizations under Medicare reassignment (form CMS-855R): Mount Auburn Professional Services Inc (NPI 1992750996, Cambridge, MA); Cambridge Public Health Commission (NPI 1487603585, Cambridge, MA); 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 27, 2015
---
Source: [NPI Profile](https://npiprofile.com/npi/1124253828) · Data from the CMS NPPES public registry.