1. Home
  2. Directory
  3. NPI Profile

MARIETTA YUMENA DE ALDAY MD
NPI 1831131424
Pediatrics in W Lancaster, CA

Active since June 11, 2006PECOS Enrolled
44256 N 10TH STREET, MOLINA MEDICAL CENTER, W LANCASTER, CA 93534(661) 723-3874(661) 723-9975 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Marietta Yumena De Alday Md NPPES

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

MARIETTA YUMENA DE ALDAY MD (NPI 1831131424) is an individual pediatrics provider in W Lancaster, California, licensed in California (A53001) and active in the NPI registry since June 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1831131424
Entity TypeIndividualFemale
Primary Taxonomy208000000X
Provider Legal NameMARIETTA YUMENA DE ALDAYCredential: MD
Location Address44256 N 10TH STREET, MOLINA MEDICAL CENTERW Lancaster, CA 93534-4134
Mailing AddressOne Golden Shore, Molina Medical Centers SmoLong Beach, CA 90802-4202 · (661) 723-3874 · Fax (661) 723-9975
Phone(661) 723-3874
Fax(661) 723-9975
Sole ProprietorNo
Enumeration DateJune 11, 2006
Last NPPES UpdateJuly 13, 2026
✔ NPI 1831131424 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPediatricsAllopathic & Osteopathic Physicians
Taxonomy Code208000000X
License✔ Licensed in CA · A53001
Definition
A pediatrician is concerned with the physical, emotional and social health of children from birth to young adulthood. Care encompasses a broad spectrum of health services ranging from preventive healthcare to the diagnosis and treatment of acute and chronic diseases. A pediatrician deals with biological, social and environmental influences on the developing child, and with the impact of disease and dysfunction on development.
44256 N 10TH STREET, W Lancaster, CA 93534
Open in Google Maps ↗

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Marietta Yumena De Alday Md 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 Reassignment

Medicare enrollment records show Marietta De Alday reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

County Of Los Angeles Auditor Controller
1.5 mi
Clinic/Center
335 E AVENUE I
Lancaster, CA 93535
  • Reassigned Medicare billing, California enrollment
  • Medicare enrollment name: County Of Los Angeles
  • 1,939 clinicians in this Medicare group
NPI 1366453045 (661) 948-8581

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 93534 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$96.36 typical visit price
range $62.96 – $187.60
Typical copayment $24.09 (range $15.74 – $46.90)
Most-billed visit code 99203
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Marietta De Alday's NPI number?

The NPI number for Marietta De Alday is 1831131424. It was assigned to this individual provider in the NPPES registry on June 11, 2006.

Where is Marietta De Alday located?

Marietta De Alday practices at 44256 N 10th Street Molina Medical Center, W Lancaster, CA 93534. The listed phone number is (661) 723-3874.

What is Marietta De Alday's specialty?

The primary specialty registered for this NPI is Pediatrics with taxonomy code 208000000X.

Is Marietta De Alday enrolled in Medicare?

Yes. Marietta De Alday is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Marietta De Alday's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Marietta De Alday reassigns Medicare benefits to County Of Los Angeles Auditor Controller (Lancaster, CA). 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 Marietta De Alday'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 Marietta De Alday was last updated on July 13, 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.