Walter Gruber, M.D.
NPI 1164440277 · Internal Medicine Physician · Midland, MI
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Walter Gruber, M.D. is a Internal Medicine Physician provider in Midland, MI (NPI 1164440277).
Provider details
- NPI number
- 1164440277
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- WG038289 (MI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
261 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 78 | $86 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 68 | $122 |
| Annual Depression Screening, 5 to 15 MinutesG0444 | 68 | $17 |
| Hemoglobin A1c Level, By Device for Home Use83037 | 28 | $10 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 19 | $53 |
Typical Medicare-allowed amounts for these services range $10–$122 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 109 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 395 | 134 |
| Losartan Potassium | 318 | 108 |
| Amlodipine Besylate | 247 | 89 |
| Levothyroxine Sodium | 242 | 73 |
| Lisinopril | 232 | 74 |
| Metformin Hclbrand: Metformin Hcl Er | 141 | 49 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-07-17
- Last updated
- 2011-10-26
Frequently asked questions
- What is Walter Gruber's NPI number?
- Walter Gruber's National Provider Identifier (NPI) is 1164440277, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Walter Gruber's specialty?
- Walter Gruber is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Walter Gruber located?
- Walter Gruber's practice location on file with NPPES is 555 W Wackerly Street, Midland, MI 48640-4712.
- What is Walter Gruber's phone number?
- The practice phone number listed in the NPPES registry for Walter Gruber is (989) 631-8300.
- Does Walter Gruber accept Medicare?
- Walter Gruber is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Walter Gruber's NPI active?
- Yes — Walter Gruber's NPI (1164440277) is active in the NPPES registry as of the last update on 2011-10-26.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.