WILLIAM K GRETZINGER (DO) – Emergency Medical Services (Emergency Medicine) Physician, NPI 1518994979

WILLIAM K GRETZINGER (DO) is a healthcare provider. based in Petoskey, Michigan. specializing in Emergency Medical Services (Emergency Medicine) Physician. They hold the professional credentials DO. They hold a License No. 5101011330 (MI). The NPI Number for WILLIAM K GRETZINGER (DO) is 1518994979

Main info

Male
35 Years Of Experience
Accepts Medicare Assignment
Name
WILLIAM K GRETZINGER (DO)
NPI
1518994979
Phone
(800) 540-8739
Address
930 SPRING STREET
Enumeration Date
28 June 2006
Last Update Date
9 October 2019

Doctor Profile

Medical School Name
MICHIGAN STATE UNIVERSITY COLLEGE OF OSTEOPATHIC MEDICINE
Secondary Phone
2316277118
Graduation Year
1991 (35 years ago)
PAC ID
5092848325
Group Practice PAC ID
3173892627
Professional Enrollment ID
I20100806000057
Data current as of
19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology
Experience61
Completeness75
Years active:19State licenses:2Digital endpointsOther names

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Provider Addresses for WILLIAM K GRETZINGER (DO)

  • 930, Spring Street, Petoskey, Emmet County, Michigan, 49770, United States

    PETOSKEY, MI 49770

    Phone: (800) 540-8739

    Fax: (616) 975-9827

    Type: Mailing

  • McLaren Northern Michigan, 416, Connable Avenue, Petoskey, Emmet County, Michigan, 49770, United States

    ER DEPARTMENT

    PETOSKEY, MI 49770

    Phone: (231) 487-4000

    Type: Location

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

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Open Payments (CMS)

CMS reports 2 Open Payments records for all available years, with a total value of $20.

Total Amount is formed as General ($20) + Research ($0) + Ownership ($0) = $20.

Last reported payment date: 2023-09-15 • Largest payer in this snapshot: Genentech USA, Inc. ($14).

Total Amount

$20

General + Research + Ownership

Payments

2

Total payment records

General Amount

$20

General payments

Research Amount

$0

Research funding

Ownership Amount

$0

Ownership interests

Ownership Count

0

Ownership records

Last Payment Date

2023-09-15

Latest reported date

Top Companies

Largest payers in this snapshot

View all Open Payments →|Open Payments Risk Radar →

Medicare Enrollment & Revalidation

Source: CMS public data · Not endorsed by CMS ·

Educational use only—not medical, billing, or legal advice.

PECOS enrollment status

Participating (accepts Medicare assignment)

Enrollment effective: 2010-08-06

PECOS data refreshed: 2026-05-27

Medicare revalidation (CMS due date list)

Due date not assigned yet

CMS is tracking this Medicare enrollment for revalidation, but has not published a due date.

Enrollment records

1

Earliest due date

Not assigned (TBD)

CMS data updated

2026-06-01

Revalidation progress

  1. Medicare enrolled
  2. On CMS revalidation list
  3. Due date assigned
  4. Revalidate in PECOS

CMS enrollment records

Enrollment IDTypeSpecialtyStateDue date
I20100806000057IEmergency MedicineMITBD

What to do next

  • No action required while the due date shows TBD.
  • Check the CMS Revalidation Lookup Tool periodically — CMS updates the list about every 60 days.
  • Do not submit a revalidation application in PECOS until CMS publishes a concrete due date.

Verify on CMS Revalidation Lookup Tool

Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS

Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

Top Medicare procedures (2023) · refreshed 2026-05-27

HCPCSDescriptionServicesBeneficiariesMedicare allowed
99285Emergency department visit with high level of medical decision making136130$0
99284Emergency department visit with moderate level of medical decision making6059$0
99291Critical care, first 30-74 minutes6057$0
View full utilization report →

Insurance plans in this area (ZIP 49770)

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Group practice members

Group practice members are other physicians who share the same Group Practice PAC ID with this doctor. When doctors form a group practice and register in PECOS as a single entity, they receive a shared identification number. This table lists all providers in the same group practice.
PAC ID: 3173892627View full group profile
NameSpecialtyState
Emergency MedicineMI
Nurse PractitionerMI
Nurse PractitionerMI
Emergency MedicineMI
Emergency MedicineOH
Emergency MedicineMI
Emergency MedicineMI
Emergency MedicinePA
-MI
-MI

Reviews

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Frequently asked questions

Does WILLIAM K GRETZINGER (DO) have a public NPI I can cite?
Public records show WILLIAM K GRETZINGER (DO) under NPI 1518994979.
Should I treat WILLIAM K GRETZINGER (DO) as an active provider?
Patients and plans typically see WILLIAM K GRETZINGER (DO) as active in the national extract.
What type of care does WILLIAM K GRETZINGER (DO) provide?
WILLIAM K GRETZINGER (DO)'s profile centers on Emergency Medical Services (Emergency Medicine) Physician. Clinical services aligned with this taxonomy classification.
Can patients visit WILLIAM K GRETZINGER (DO) in Petoskey, Michigan?
For routing, start with Petoskey, Michigan for WILLIAM K GRETZINGER (DO), then verify phone and hours locally.
Why is information missing for WILLIAM K GRETZINGER (DO)?
Providers choose how much contact data to publish. Missing fields do not mean the profile is fake.

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