1. Home
  2. Directory
  3. Texas
  4. Austin
  5. Pediatrics
  6. NPI Profile

DR. EILEEN MERKLE STEWART M.D.
NPI 1245403146
Pediatrics - Pediatric Cardiology in Austin, TX

Active since April 11, 2008PECOS Enrolled
4314 MEDICAL PARKWAY, SUITE 200, AUSTIN, TX 78756(512) 454-1110 Get Directions Write a Review

NPPES record last updated: October 3, 2016. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Eileen Merkle Stewart M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. EILEEN MERKLE STEWART M.D. (NPI 1245403146) is an individual pediatric cardiology provider in Austin, Texas, licensed in Texas (Q3444) and active in the NPI registry since April 2008. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1245403146
Entity TypeIndividualFemale
Primary Taxonomy2080P0202X
Provider Legal NameDR. EILEEN MERKLE STEWARTCredential: M.D.
Location Address4314 MEDICAL PARKWAY, SUITE 200Austin, TX 78756
Mailing Address4314 Medical Parkway, Suite 200Austin, TX 78756 · (512) 454-1110
Phone(512) 454-1110
Sole ProprietorNo
Enumeration DateApril 11, 2008
Last NPPES UpdateOctober 3, 2016
✔ NPI 1245403146 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyPediatrics · Pediatric CardiologyAllopathic & Osteopathic Physicians
Taxonomy Code2080P0202X
License✔ Licensed in TX · Q3444
Definition
A pediatric cardiologist provides comprehensive care to patients with cardiovascular problems. This specialist is skilled in selecting, performing and evaluating the structural and functional assessment of the heart and blood vessels, and the clinical evaluation of cardiovascular disease.
Also ListedPediatricsTaxonomy 208000000X · License N/A (NM)
4314 MEDICAL PARKWAY, Austin, TX 78756
Open in Google Maps ↗

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Texas, Harbor Health, Moda Health Plan, Inc. and more.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. Eileen Merkle Stewart M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

2

Medicare enrollment records show Eileen Stewart reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Dell Children's Medical Group
2.2 mi
Pediatrics
1301 BARBARA JORDAN BLVD STE 200
Austin, TX 78723
  • Reassigned Medicare billing, Texas enrollment
  • Medicare enrollment name: Dell Childrens Medical Group
  • 576 clinicians in this Medicare group
NPI 1326072943 (512) 628-1800
Magella Medical Associates Billing, Inc.
14 mi
Neonatal-Perinatal Medicine
2400 ROUND ROCK AVE
Round Rock, TX 78681
  • Reassigned Medicare billing, Texas enrollment
  • 432 clinicians in this Medicare group
NPI 1083631071 (512) 341-1000

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

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 Eileen Stewart's NPI number?

The NPI number for Eileen Stewart is 1245403146. It was assigned to this individual provider in the NPPES registry on April 11, 2008.

Where is Eileen Stewart located?

Eileen Stewart practices at 4314 Medical Parkway Suite 200, Austin, TX 78756. The listed phone number is (512) 454-1110.

What is Eileen Stewart's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Cardiology, with taxonomy code 2080P0202X.

Is Eileen Stewart enrolled in Medicare?

Yes. Eileen Stewart is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Eileen Stewart's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Eileen Stewart reassigns Medicare benefits to 2 organizations: Dell Children's Medical Group (Austin, TX) and Magella Medical Associates Billing, Inc. (Round Rock, TX). 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 Eileen Stewart's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Eileen Stewart accept?

Health plans from Blue Cross and Blue Shield of Texas, Harbor Health, Moda Health Plan, Inc., Oscar Health and Oscar Insurance Company and 1 other insurer list Eileen Stewart 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 Eileen Stewart was last updated on October 3, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.