STEPHEN GABRIEL SIMMER MD
NPI 1972953917
Internal Medicine - Gastroenterology in Grand Rapids, MI
About Stephen Gabriel Simmer Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
STEPHEN GABRIEL SIMMER MD (NPI 1972953917) is an individual gastroenterology provider in Grand Rapids, Michigan, licensed in Michigan (4301117308) and active in the NPI registry since June 2016. He is enrolled in Medicare PECOS, is affiliated with Corewell Health Zeeland Hospital, and is a graduate of Wayne State University School Of Medicine (2016).
NPPES Registry Identity
Specialties & Licenses 2
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Stephen Gabriel Simmer Md 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.
Medicare Billing Reassignments
2Medicare enrollment records show Stephen Simmer reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Grand Rapids, MI 49546
- Reassigned Medicare billing, Michigan enrollment
- 2,446 clinicians in this Medicare group
Saint Joseph, MI 49085
- Reassigned Medicare billing, Michigan enrollment
- 724 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 7
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.
Hospital Affiliations CMS Care Compare 3
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Corewell Health Zeeland Hospital
Acute Care Hospitals · Zeeland, MISpectrum Health
Acute Care Hospitals · Grand Rapids, MICorewell Health Pennock Hospital
Critical Access Hospitals · Hastings, MIPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 49546 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
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.
GRAND RAPIDS, MI 49546
GRAND RAPIDS, MI 49546
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 Stephen Simmer's NPI number?
The NPI number for Stephen Simmer is 1972953917. It was assigned to this individual provider in the NPPES registry on June 21, 2016.
Where is Stephen Simmer located?
Stephen Simmer practices at 4100 Lake Dr SE Ste 205, Grand Rapids, MI 49546. The listed phone number is (616) 267-7414.
What is Stephen Simmer's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.
Is Stephen Simmer enrolled in Medicare?
Yes. Stephen Simmer 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.
Which organizations bill Medicare for Stephen Simmer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Stephen Simmer reassigns Medicare benefits to 2 organizations: Spectrum Health Primary Care Partners (Grand Rapids, MI) and Lakeland Medical Practices (Saint Joseph, MI). Each 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 Stephen Simmer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Stephen Simmer accept?
Health plans from Ambetter Health, Ambetter from Buckeye Health Plan, Ambetter from Meridian, Blue Care Network of Michigan and Blue Cross Blue Shield of Michigan Mutual Insurance Company and 1 other insurer list Stephen Simmer 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 Stephen Simmer affiliated with any hospitals?
According to CMS data, Stephen Simmer is affiliated with Corewell Health Zeeland Hospital, Spectrum Health and Corewell Health Pennock Hospital.
When was this NPI record last updated?
The NPPES record for Stephen Simmer was last updated on July 31, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.
# Stephen Gabriel Simmer, MD · NPI 1972953917
Gastroenterology physician in Grand Rapids, Michigan. Individual provider, active in the CMS NPPES registry since June 21, 2016.
## Identity
- **NPI:** 1972953917 (Entity type: Individual)
- **Enumerated:** June 21, 2016
- **Primary specialty:** Internal Medicine - Gastroenterology · taxonomy 207RG0100X
- **State license:** 4301117308 (Michigan)
- **Sole proprietor:** No
## Practice location
- **Address:** 4100 LAKE DR SE STE 205, Grand Rapids, MI 49546-8292
- **Phone:** (616) 267-7414
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Spectrum Health Primary Care Partners (NPI 1528374683, Grand Rapids, MI); Lakeland Medical Practices (NPI 1538397120, Saint Joseph, MI) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Wayne State University School Of Medicine, class of 2016
## Record status
- **NPPES last updated:** July 31, 2023
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Source: [NPI Profile](https://npiprofile.com/npi/1972953917) · Data from the CMS NPPES public registry.