Stephan Grigorian, M.D.
NPI 1821129057 · Anatomic Pathology & Clinical Pathology Physician · Corona, CA
Enrolled with Medicare as Practitioner - Pathology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Stephan Grigorian, M.D. is a Anatomic Pathology & Clinical Pathology Physician provider in Corona, CA (NPI 1821129057).
Provider details
- NPI number
- 1821129057
- Entity type
- Individual
- Primary specialty
- Anatomic Pathology & Clinical Pathology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- A88170 (CA)
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
2,679 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) |
|---|---|---|
| Pathology Examination of Tissue Using a Microscope, Intermediate Complexity88305 | 805 | $36 |
| Special Stained Specimen Slides to Examine Tissue, Each Additional Procedure88341 | 515 | $27 |
| Special Stained Specimen Slides to Examine Tissue Including Interpretation and Report88313 | 296 | $12 |
| Special Stained Specimen Slides to Examine Tissue, Initial Procedure88342 | 257 | $34 |
| Preparation of Tissue for Examination By Removing Any Calcium Present88311 | 156 | $12 |
| Cell Examination of Body Fluid, Smears88104 | 149 | $27 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-08
- Last updated
- 2022-08-29
- Certified
- 2022-08-29
Frequently asked questions
- What is Stephan Grigorian's NPI number?
- Stephan Grigorian's National Provider Identifier (NPI) is 1821129057, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Stephan Grigorian's specialty?
- Stephan Grigorian is listed in the NPPES registry with a primary specialty of Anatomic Pathology & Clinical Pathology Physician (Allopathic & Osteopathic Physicians).
- Where is Stephan Grigorian located?
- Stephan Grigorian's practice location on file with NPPES is 800 S Main St, Corona, CA 92882-3420.
- What is Stephan Grigorian's phone number?
- The practice phone number listed in the NPPES registry for Stephan Grigorian is (858) 877-0267.
- Does Stephan Grigorian accept Medicare?
- Stephan Grigorian is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Stephan Grigorian's NPI active?
- Yes — Stephan Grigorian's NPI (1821129057) is active in the NPPES registry as of the last update on 2022-08-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.