DR. MARK FRANCIS GRENQUIST DO
NPI 1942300454
Internal Medicine in Chelsea, MI

Q: What is Mark Grenquist's NPI number?

The NPI number for Mark Grenquist is 1942300454. It was assigned to this individual provider in the NPPES registry on September 24, 2006.

Q: What is Mark Grenquist's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Mark Grenquist was last updated on September 6, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 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.

Active since September 24, 2006PECOS EnrolledAccepts Medicare Assignment

775 S MAIN ST, CHELSEA, MI 48118(734) 593-6000 Get Directions Write a Review

NPPES record last updated: September 6, 2016. Verified against the NPPES registry weekly; last sync: August 30, 2026.

On this page

About Dr. Mark Francis Grenquist Do NPPES

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

DR. MARK FRANCIS GRENQUIST DO (NPI 1942300454) is an individual internal medicine provider in Chelsea, Michigan, licensed in Michigan (5101014936) and active in the NPI registry since September 2006. He is enrolled in Medicare PECOS, is affiliated with Borgess Medical Center, and is a graduate of Michigan State University College Of Human Medicine (2001).

NPPES Registry Identity

NPI1942300454

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameDR. MARK FRANCIS GRENQUISTCredential: DO

Location Address775 S MAIN STChelsea, MI 48118-1383

Mailing Address24 Frank Lloyd Wright Dr, Po Box 0446 - Lobby JAnn Arbor, MI 48105-9484 · (734) 747-6766 · Fax (734) 222-3100

Phone(734) 593-6000

Sole ProprietorNo

Medical School CMSMichigan State University College Of Human MedicineGraduated 2001

Enumeration DateSeptember 24, 2006

Last NPPES UpdateSeptember 6, 2016

✔ NPI 1942300454 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in MI · 5101014936

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

Also ListedHospitalistTaxonomy 208M00000X · License 5101014936 (MI)

775 S MAIN ST, Chelsea, MI 48118

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Other Identifiers 8

Medicaid1942300454MI

Medicare PINC97618303 - BRONSONMI

Medicare PINM77890010MI

Medicare PIN0M32310MI

Medicaid4631106MI

Other1417961137MI · Bcbsm - Bronson Battle Creek

Other5331090MI · Bcbs Individual Pin

Medicare UPINI18298MI

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

Dr. Mark Francis Grenquist Do 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 ID9032179866

PECOS Enrollment IDI20041015000099

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.

Areas of Expertise CMS Part B claims 4

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

187 services79 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

67 services64 patients

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222

Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.

32 services31 patients

Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223

Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.

13 services13 patients

Hospital Affiliations CMS Care Compare 2

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

Borgess Medical Center

Acute Care Hospitals · Kalamazoo, MI

4/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number230117

Location1521 Gull RoadKalamazoo, MI 49048 · Kalamazoo County

Emergency services Birthing friendly

Oaklawn Hospital

Acute Care Hospitals · Marshall, MI

4/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number230217

Location200 N MadisonMarshall, MI 49068 · Calhoun County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 48118 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

$134.28 typical visit price

range $58.04 – $177.36

Typical copayment $33.57 (range $14.51 – $44.34)

Most-billed visit code 99204

Established Patient

$102.35 typical visit price

range $18.32 – $143.49

Typical copayment $25.58 (range $4.58 – $35.87)

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.

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Portable gaseous oxygen system, rental; includes portable container, regulator, flowmeter, humidifier, cannula or mask, and tubing E0431

DME-Oxygen and Supplies · category DC000N

1 supplier12 claims12 services$17.63 avg. paid by Medicare

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390

DME-Oxygen and Supplies · category DC002N

1 supplier12 claims12 services$87.06 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

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.

MR. LESLIE JOHN BABBITT III AT, ATC

Specialist/Technologist (Athletic Trainer)