Stanley Tan, MD
NPI 1396747721 · Endocrinology, Diabetes & Metabolism Physician · Castro Valley, CA
Enrolled with Medicare as Practitioner - Endocrinology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Stanley Tan, MD is a Endocrinology, Diabetes & Metabolism Physician provider in Castro Valley, CA (NPI 1396747721).
Provider details
- NPI number
- 1396747721
- Entity type
- Individual
- Primary specialty
- Endocrinology, Diabetes & Metabolism PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- G23082 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
3 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
173 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 | 72 | $109 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 48 | $154 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 23 | $130 |
| Injection of Drug Or Substance Under Skin Or Into Muscle96372 | 18 | $18 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 12 | $70 |
Typical Medicare-allowed amounts for these services range $18–$154 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, 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 · 6 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 41 | 28 |
| Glipizide | 15 | 15 |
| Empagliflozinbrand: Jardiance | 15 | — |
| Glimepiride | 13 | — |
| Denosumabbrand: Prolia | 13 | 13 |
| Dulaglutidebrand: Trulicity | 11 | — |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means , never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Practice location
Mailing address
Additional practice locations (2)
- 1005 W Circle StAvon Park, FL 33825-2928Phone: (863) 453-5500Fax: (863) 453-5566
- 7125 Murrell RdMelbourne, FL 32940-7999Phone: (321) 215-4910Fax: (321) 434-4361
Registry dates
- Enumerated
- 2005-08-15
- Last updated
- 2025-10-08
- Certified
- 2025-10-08
Frequently asked questions
- What is Stanley Tan's NPI number?
- Stanley Tan's National Provider Identifier (NPI) is 1396747721, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Stanley Tan's specialty?
- Stanley Tan is listed in the NPPES registry with a primary specialty of Endocrinology, Diabetes & Metabolism Physician (Allopathic & Osteopathic Physicians).
- Where is Stanley Tan located?
- Stanley Tan's practice location on file with NPPES is 20642 John Dr, Castro Valley, CA 94546-5103.
- What is Stanley Tan's phone number?
- The practice phone number listed in the NPPES registry for Stanley Tan is (510) 785-5000.
- Does Stanley Tan accept Medicare?
- Stanley Tan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Stanley Tan's NPI active?
- Yes — Stanley Tan's NPI (1396747721) is active in the NPPES registry as of the last update on 2025-10-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.