Quick answers
- Which hospitals does Justin Triemstra work at?
- Medicare's official clinician data lists Justin Triemstra at 1 hospital: Spectrum Health. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Justin Triemstra see patients?
- Medicare's clinician data lists 2 practice locations, including Grand Rapids, MI and Kentwood, MI. Call before your visit to confirm the address.
- What is Justin Triemstra's specialty?
- Medicare lists Pediatric Medicine as the primary specialty.
- Does Justin Triemstra accept Medicare assignment?
- Yes. Medicare's clinician data says Justin Triemstra accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for Justin Triemstra?
- (616) 391-5600, as listed in official Medicare / NPI Registry data.
- What is Justin Triemstra's NPI number?
- 1588002661. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Justin Triemstra works
Medicare's Facility Affiliation Data lists Justin Triemstra at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Spectrum HealthGrand Rapids, MI · Acute Care Hospital · CCN 230038
Practice locations
Addresses where Justin Triemstra is enrolled with Medicare (CMS data updated 2026-10-02).
- 4100 Lake Dr SEGrand Rapids, MI 49546
- 4444 Kalamazoo Ave SE, 200 Corewell Health Medical Group WestKentwood, MI 49508 (616) 391‑5600
Group practices
Medicare enrollment lists Justin Triemstra as a member of this group (CMS data updated 2026-10-02).
- Spectrum Health Primary Care Partners2,294 clinicians in the group
Specialties
- Pediatric Medicineprimary
Other pediatricians in Grand Rapids
Clinicians with the same Medicare primary specialty in Grand Rapids, MI — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Loyola University Of Chicago, Stritch School Of Medicine |
| Graduation year | 2013 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1588002661 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians