Benjamin Chang, MD
NPI 1639185143 · Hospitalist Physician · Mountain View, CA
Enrolled with Medicare as Practitioner - Hospitalist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Benjamin Chang, MD is a Hospitalist Physician provider in Mountain View, CA (NPI 1639185143).
Provider details
- NPI number
- 1639185143
- Entity type
- Individual
- Primary specialty
- Hospitalist PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A70755 (CA)
Specialties & taxonomies
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
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
817 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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 246 | $89 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 238 | $133 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 192 | $131 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 107 | $195 |
| Subsequent Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 25 Minutes99231 | 21 | $55 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 |
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 |
|---|---|---|
| Furosemide | 19 | 12 |
| Metoprolol Succinate | 15 | — |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 14 | 14 |
| Apixabanbrand: Eliquis | 12 | — |
| Cephalexin | 11 | 11 |
| Pantoprazole Sodium | 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
Registry dates
- Enumerated
- 2006-08-01
- Last updated
- 2021-02-22
- Certified
- 2021-02-22
Frequently asked questions
- What is Benjamin Chang's NPI number?
- Benjamin Chang's National Provider Identifier (NPI) is 1639185143, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Benjamin Chang's specialty?
- Benjamin Chang is listed in the NPPES registry with a primary specialty of Hospitalist Physician (Allopathic & Osteopathic Physicians).
- Where is Benjamin Chang located?
- Benjamin Chang's practice location on file with NPPES is 701 E El Camino Real, Mountain View, CA 94040-2833.
- What is Benjamin Chang's phone number?
- The practice phone number listed in the NPPES registry for Benjamin Chang is (650) 934-7000.
- Does Benjamin Chang accept Medicare?
- Benjamin Chang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Benjamin Chang's NPI active?
- Yes — Benjamin Chang's NPI (1639185143) is active in the NPPES registry as of the last update on 2021-02-22.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.