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MARY KAY WILLIAMS NURSE PRACTITIONER
NPI 1366461121
Nurse Practitioner in Traverse City, MI

Active since July 19, 2006PECOS Enrolled
100/100
CMS Quality Rating
1221 SIXTH ST STE 306, TRAVERSE CITY, MI 49684(231) 935-2400(231) 392-2424 Get Directions Write a Review

NPPES record last updated: December 31, 2020. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Dec 31, 2020, Apr 11, 2019 (2 updates tracked since 2019).

About Mary Kay Williams Nurse Practitioner NPPES

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

MARY KAY WILLIAMS NURSE PRACTITIONER (NPI 1366461121) is an individual nurse practitioner in Traverse City, Michigan, licensed in Michigan (4704123296) and active in the NPI registry since July 2006. She is enrolled in Medicare PECOS and maintains a secondary practice location in Traverse City.

NPPES Registry Identity

NPI1366461121
Entity TypeIndividualFemale
Primary Taxonomy363L00000X
Provider Legal NameMARY KAY WILLIAMSCredential: NURSE PRACTITIONER
Location Address1221 SIXTH ST STE 306Traverse City, MI 49684-2361
Mailing Address701 W Front St, Ste 200Traverse City, MI 49684-2236 · (231) 346-4023 · Fax (231) 932-7311
Phone(231) 935-2400
Fax(231) 392-2424
Sole ProprietorNo
Enumeration DateJuly 19, 2006
Last NPPES UpdateDecember 31, 20202 updates tracked since enumeration
NPPES CertifiedDecember 31, 2020
✔ NPI 1366461121 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363L00000X
License✔ Licensed in MI · 4704123296
Definition
(1) A registered nurse provider with a graduate degree in nursing prepared for advanced practice involving independent and interdependent decision making and direct accountability for clinical judgment across the health care continuum or in a certified specialty. (2) A registered nurse who has completed additional training beyond basic nursing education and who provides primary health care services in accordance with state nurse practice laws or statutes. Tasks performed by nurse practitioners vary with practice requirements mandated by geographic, political, economic, and social factors. Nurse practitioner specialists include, but are not limited to, family nurse practitioners, gerontological nurse practitioners, pediatric nurse practitioners, obstetric-gynecologic nurse practitioners, and school nurse practitioners.
1221 SIXTH ST STE 306, Traverse City, MI 49684
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Secondary Practice Location 1

Location 1701 W Front St, STE 200Traverse City, MI 49684-2236 · Phone (231) 346-4023 · Fax (231) 932-7311

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Priority Health.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mary Kay Williams Nurse Practitioner 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 Mary Williams reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Munson Medical Center
Same address
Endocrinology, Diabetes & Metabolism
1221 SIXTH ST STE 208
Traverse City, MI 49684
  • Reassigned Medicare billing, Michigan enrollment
  • 492 clinicians in this Medicare group
NPI 1083761860 (231) 935-2045

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 49684 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
$84.74 typical visit price
range $54.34 – $166.68
Typical copayment $21.18 (range $13.58 – $41.67)
Most-billed visit code 99203
Established Patient
$96.44 typical visit price
range $17.09 – $135.40
Typical copayment $24.11 (range $4.27 – $33.85)
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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

100/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Promoting Interoperability100
Improvement Activities40

Other Providers at the Same Location NPPES

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

BRITTNEE KEYES FNP
Nurse Practitioner (Family)
1221 SIXTH ST STE 306
TRAVERSE CITY, MI 49684
Grand Traverse County (231) 935-2400

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 Mary Williams's NPI number?

The NPI number for Mary Williams is 1366461121. It was assigned to this individual provider in the NPPES registry on July 19, 2006.

Where is Mary Williams located?

Mary Williams practices at 1221 Sixth St Ste 306, Traverse City, MI 49684. The listed phone number is (231) 935-2400.

What is Mary Williams's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Is Mary Williams enrolled in Medicare?

Yes. Mary Williams is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mary Williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mary Williams reassigns Medicare benefits to Munson Medical Center (Traverse City, MI). 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 Mary Williams's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mary Williams accept?

Health plans from Priority Health list Mary Williams 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 Mary Williams was last updated on December 31, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 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.