DR. GERALD ROSS MARX MD
NPI 1063403384
Pediatrics - Pediatric Cardiology in Boston, MA
About Dr. Gerald Ross Marx Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. GERALD ROSS MARX MD (NPI 1063403384) is an individual pediatric cardiology provider in Boston, Massachusetts, licensed in Texas (W7367) and active in the NPI registry since November 2005. He is enrolled in Medicare PECOS and maintains a secondary practice location in San Antonio.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
Other Identifiers 2
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Dr. Gerald Ross Marx Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Gerald Marx reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
San Antonio, TX 78207
- Reassigned Medicare billing, Texas enrollment
- 453 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 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 Gerald Marx's NPI number?
The NPI number for Gerald Marx is 1063403384. It was assigned to this individual provider in the NPPES registry on November 4, 2005.
Where is Gerald Marx located?
Gerald Marx practices at 300 Longwood Ave, Boston, MA 02115. The listed phone number is (617) 355-0039.
What is Gerald Marx's specialty?
The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Cardiology, with taxonomy code 2080P0202X.
Is Gerald Marx enrolled in Medicare?
Yes. Gerald Marx is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Gerald Marx's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Gerald Marx reassigns Medicare benefits to Baylor College Of Medicine (San Antonio, TX). 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 Gerald Marx's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Gerald Marx accept?
Health plans from Blue Cross and Blue Shield of Texas, Oscar Insurance Company and WellPoint list Gerald Marx 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 Gerald Marx was last updated on June 29, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 months 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. Gerald Ross Marx, MD · NPI 1063403384
Pediatric Cardiology physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since November 4, 2005.
## Identity
- **NPI:** 1063403384 (Entity type: Individual)
- **Enumerated:** November 4, 2005
- **Primary specialty:** Pediatrics - Pediatric Cardiology · taxonomy 2080P0202X
- **State license:** W7367 (Texas)
- **Sole proprietor:** No
## Practice location
- **Address:** 300 LONGWOOD AVE, Boston, MA 02115-5724
- **Phone:** (617) 355-0039
## 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:** Baylor College Of Medicine (NPI 1285079764, San Antonio, TX), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** June 29, 2026
- **Other identifiers:** Medicaid 3038831 (MA); Medicaid GM27010 (RI)
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Source: [NPI Profile](https://npiprofile.com/npi/1063403384) · Data from the CMS NPPES public registry.