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DR. MARIEL CASTILLO MD
NPI 1326139700
Pediatrics in Mount Vernon, WA

Active since September 28, 2006PECOS Enrolled
2320 FREEWAY DR, MOUNT VERNON, WA 98273(360) 814-6870(360) 814-6871 Get Directions Write a Review

NPPES record last updated: March 29, 2018. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Mariel Castillo Md NPPES

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

DR. MARIEL CASTILLO MD (NPI 1326139700) is an individual pediatrics provider in Mount Vernon, Washington, licensed in Washington (MD60091777) and active in the NPI registry since September 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1326139700
Entity TypeIndividualFemale
Primary Taxonomy208000000X
Provider Legal NameDR. MARIEL CASTILLOCredential: MD
Location Address2320 FREEWAY DRMount Vernon, WA 98273-5445
Mailing Address1400 E. Kincaid StreetMount Vernon, WA 98274-4127 · (360) 428-2500 · Fax (360) 428-6485
Phone(360) 814-6870
Fax(360) 814-6871
Sole ProprietorNo
Enumeration DateSeptember 28, 2006
Last NPPES UpdateMarch 29, 2018
✔ NPI 1326139700 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPediatricsAllopathic & Osteopathic Physicians
Taxonomy Code208000000X
License✔ Licensed in WA · MD60091777
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.
2320 FREEWAY DR, Mount Vernon, WA 98273
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Other Names 1

Former Name (1)Dr. Mariel Castillo-guanzon Md

Other Identifiers 1

Other263681WA · Labor & Industries

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Cigna Healthcare, Premera Blue Cross Blue Shield of Alaska, Providence Health Plan.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. Mariel Castillo 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 Mariel Castillo reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Public Hospital Dist No 1 Skagit
1.2 mi
Physical Therapist
1901 HOAG ROAD, SUITE B
Mount Vernon, WA 98273
  • Reassigned Medicare billing, Washington enrollment
  • 463 clinicians in this Medicare group
NPI 1811460652 (360) 814-2184

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 98273 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
$88.29 typical visit price
range $57.27 – $172.80
Typical copayment $22.07 (range $14.31 – $43.20)
Most-billed visit code 99203
Established Patient
$100.78 typical visit price
range $18.56 – $141.11
Typical copayment $25.19 (range $4.64 – $35.27)
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.

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.

DR. MICHAEL ARMANDO MARCHETTI M.D.
Dermatology
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6810
MISS CARA ALEXANDRA WALKER PA-C
Physician Assistant (Surgical)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6800
KEIRSTEN DEANNE MONTGOMERY RN, BSN, FNP-C
Nurse Practitioner (Family)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6315
DAVID MICHAEL MOURNING M.D.
Orthopaedic Surgery (Orthopaedic Surgery of the Spine)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6800
PAULA ANDRADE WOLFF ARNP
Nurse Practitioner (Family)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6850
ASHTON TAYLOR DE CARDENAS PA-C
Physician Assistant (Surgical)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6800
MR. LUKE M WALTERS PA-C
Physician Assistant (Medical)
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6810
ALEXANDER WILLIS M.D.
Orthopaedic Surgery
2320 FREEWAY DR
MOUNT VERNON, WA 98273
Skagit County (360) 814-6800

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 Mariel Castillo's NPI number?

The NPI number for Mariel Castillo is 1326139700. It was assigned to this individual provider in the NPPES registry on September 28, 2006. The provider is also known as Dr. Mariel Castillo-Guanzon MD.

Where is Mariel Castillo located?

Mariel Castillo practices at 2320 Freeway Dr, Mount Vernon, WA 98273. The listed phone number is (360) 814-6870.

What is Mariel Castillo's specialty?

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

Is Mariel Castillo enrolled in Medicare?

Yes. Mariel Castillo is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mariel Castillo's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mariel Castillo reassigns Medicare benefits to Public Hospital Dist No 1 Skagit (Mount Vernon, WA). 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 Mariel Castillo's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mariel Castillo accept?

Health plans from Cigna Healthcare, Premera Blue Cross Blue Shield of Alaska and Providence Health Plan list Mariel Castillo 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 Mariel Castillo was last updated on March 29, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.