Ray Hsiao, MD
NPI 1164507869 · Internal Medicine Physician · Hacienda Heights, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Ray Hsiao, MD is a Internal Medicine Physician provider in Hacienda Heights, CA (NPI 1164507869).
Provider details
- NPI number
- 1164507869
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G70571 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
16,693 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Chronic Care Management Services, First 20 Minutes of Clinical Staff Time Directed By Health Care Professional, Per Calendar Month99490 | 3,616 | $68 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 3,153 | $17 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 2,792 | $99 |
| Chronic Care Management Services for Two Or More Chronic Conditions, Additional 20 Minutes of Clinical Staff Time Directed By Health Care Professional, Per Calendar Month99439 | 2,655 | $52 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 1,196 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 178 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Rosuvastatin Calcium | 1,085 | 371 |
| Amlodipine Besylate | 1,015 | 316 |
| Atorvastatin Calcium | 1,009 | 282 |
| Ezetimibe | 873 | 289 |
| Losartan Potassium | 858 | 256 |
| Metoprolol Succinate | 398 | 116 |
| Dapagliflozin Propanediol |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$2,362 across 103 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-10-25
- Last updated
- 2007-07-09
Frequently asked questions
- What is Ray Hsiao's NPI number?
- Ray Hsiao's National Provider Identifier (NPI) is 1164507869, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ray Hsiao's specialty?
- Ray Hsiao is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Ray Hsiao located?
- Ray Hsiao's practice location on file with NPPES is 1850 S Azusa Ave, Hacienda Heights, CA 91745-6813.
- What is Ray Hsiao's phone number?
- The practice phone number listed in the NPPES registry for Ray Hsiao is (626) 854-7866.
- Does Ray Hsiao accept Medicare?
- Ray Hsiao is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Ray Hsiao's NPI active?
- Yes — Ray Hsiao's NPI (1164507869) is active in the NPPES registry as of the last update on 2007-07-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.