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MARQUETTA WILLIAMSON ARNP
NPI 1487127742
Nurse Practitioner - Psychiatric/Mental Health in Seattle, WA

Active since January 09, 2019PECOS EnrolledAccepts Medicare Assignment
325 9TH AVE, SEATTLE, WA 98104(206) 520-5000 Get Directions Write a Review

NPPES record last updated: July 29, 2025. Verified against the NPPES registry weekly; last sync: August 30, 2026.

Record update history: May 8, 2025, Oct 5, 2021, Feb 12, 2019 and 1 more (4 updates tracked since 2019).

About Marquetta Williamson Arnp NPPES

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

MARQUETTA WILLIAMSON ARNP (NPI 1487127742) is an individual psychiatric/mental health provider in Seattle, Washington, licensed in Washington (AP61643314) and active in the NPI registry since January 2019. She is enrolled in Medicare PECOS, is affiliated with Harborview Medical Center, and is a graduate of Other (2019).

NPPES Registry Identity

NPI1487127742
Entity TypeIndividualFemale
Primary Taxonomy363LP0808X
Provider Legal NameMARQUETTA WILLIAMSONCredential: ARNP
Location Address325 9TH AVESeattle, WA 98104-2420
Mailing AddressPo Box 50095Seattle, WA 98145-5095 · (206) 520-5700
Phone(206) 520-5000
Sole ProprietorNo
Medical School CMSOtherGraduated 2019
Enumeration DateJanuary 9, 2019
Last NPPES UpdateJuly 29, 20254 updates tracked since enumeration
NPPES CertifiedJuly 29, 2025
✔ NPI 1487127742 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Practitioner · Psychiatric/Mental HealthPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363LP0808X
Licenses✔ Licensed in WA · AP61643314✔ Licensed in NE · 112714
325 9TH AVE, Seattle, WA 98104
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 Nebraska, Medica, Oscar Insurance Company and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Marquetta Williamson Arnp is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID6901131002
PECOS Enrollment IDI20250625003908
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.

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Harborview Medical Center

Acute Care Hospitals · Seattle, WA
1/5 CMS rating
OwnershipGovernment - Local
CMS Certification Number500064
Location325 9th AvenueSeattle, WA 98104 · King County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 98104 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
$97.43 typical visit price
range $63.67 – $189.37
Typical copayment $24.35 (range $15.91 – $47.34)
Most-billed visit code 99203
Established Patient
$111.00 typical visit price
range $21.12 – $155.00
Typical copayment $27.75 (range $5.28 – $38.75)
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.

SANDRA K WALKER ARNP
Nurse Practitioner (Acute Care)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 598-0502
JULIA J VISSER DPT
Physical Therapist
325 9TH AVE, BOX 359920
SEATTLE, WA 98104
King County (206) 744-1675
GENIA J MONCADA
Pharmacist
325 9TH AVE, MAILSTOP 359912
SEATTLE, WA 98104
King County (206) 731-3219
JACQUELINE M. KIM LICSW, MSW
Social Worker (Clinical)
325 9TH AVE, BOX 359760
SEATTLE, WA 98104
King County (206) 744-8511
MS. DIANE E WHEELER MS, PA-C
Physician Assistant (Medical)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 744-3000
AMELIA V. RIVERA
Physical Therapist
325 9TH AVE
SEATTLE, WA 98104
King County (206) 774-3300
TIMOTHY WILLIAM MENZA MD, PHD
Internal Medicine (Infectious Disease)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 520-5000
DEMETRIOS TEREZAKIS
Occupational Therapist
325 9TH AVE
SEATTLE, WA 98104
King County (206) 744-6112

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 Marquetta Williamson's NPI number?

The NPI number for Marquetta Williamson is 1487127742. It was assigned to this individual provider in the NPPES registry on January 9, 2019.

Where is Marquetta Williamson located?

Marquetta Williamson practices at 325 9th Ave, Seattle, WA 98104. The listed phone number is (206) 520-5000.

What is Marquetta Williamson's specialty?

The primary specialty registered for this NPI is Nurse Practitioner, specializing in Psychiatric/Mental Health, with taxonomy code 363LP0808X.

Is Marquetta Williamson enrolled in Medicare?

Yes. Marquetta Williamson is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Marquetta Williamson accept?

Health plans from Blue Cross and Blue Shield of Nebraska, Medica, Oscar Insurance Company, Premera Blue Cross Blue Shield of Alaska and UnitedHealthcare list Marquetta Williamson 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.

Is Marquetta Williamson affiliated with any hospitals?

According to CMS data, Marquetta Williamson is affiliated with Harborview Medical Center.

When was this NPI record last updated?

The NPPES record for Marquetta Williamson was last updated on July 29, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.