Gregory Granzeier, DO
NPI 1134239320 · Obstetrics & Gynecology Physician · Roscoe, IL
Enrolled with Medicare as Practitioner - Obstetrics/Gynecology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gregory Granzeier, DO is a Obstetrics & Gynecology Physician provider in Roscoe, IL (NPI 1134239320).
Provider details
- NPI number
- 1134239320
- Entity type
- Individual
- Primary specialty
- Obstetrics & Gynecology PhysicianAllopathic & Osteopathic Physicians
- Credential
- DO
- Sex
- Male
- Sole proprietor
- No
- License
- 036-094024 (IL)
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
12 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) |
|---|---|---|
| Cervical Or Vaginal Cancer Screening; Pelvic and Clinical Breast ExaminationG0101 | 12 | $28 |
Typical Medicare-allowed amounts for these services range $28–$28 (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.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-30
- Last updated
- 2010-01-21
Frequently asked questions
- What is Gregory Granzeier's NPI number?
- Gregory Granzeier's National Provider Identifier (NPI) is 1134239320, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Granzeier's specialty?
- Gregory Granzeier is listed in the NPPES registry with a primary specialty of Obstetrics & Gynecology Physician (Allopathic & Osteopathic Physicians).
- Where is Gregory Granzeier located?
- Gregory Granzeier's practice location on file with NPPES is 5000 Prairie Rose Dr, Roscoe, IL 61073-7792.
- What is Gregory Granzeier's phone number?
- The practice phone number listed in the NPPES registry for Gregory Granzeier is (815) 971-2000.
- Does Gregory Granzeier accept Medicare?
- Gregory Granzeier is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gregory Granzeier's NPI active?
- Yes — Gregory Granzeier's NPI (1134239320) is active in the NPPES registry as of the last update on 2010-01-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.