William Klein, MD
NPI 1205834819 · Internal Medicine Physician · Newport Beach, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Klein, MD is a Internal Medicine Physician provider in Newport Beach, CA (NPI 1205834819).
Provider details
- NPI number
- 1205834819
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G14712 (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
20 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
1,498 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 706 | $147 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 225 | $206 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 212 | $151 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report93000 | 144 | $17 |
| Test to Measure Expiratory Airflow and Volume94010 | 134 | $33 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 98 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 283 | 83 |
| Levothyroxine Sodium | 278 | 79 |
| Fluticasone/Umeclidin/Vilanterbrand: Trelegy Ellipta | 250 | 61 |
| Amlodipine Besylate | 211 | 60 |
| Rosuvastatin Calcium | 194 | 57 |
| Tamsulosin Hcl | 180 | 50 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$2,071 across 99 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
- 2005-07-08
- Last updated
- 2008-01-17
Frequently asked questions
- What is William Klein's NPI number?
- William Klein's National Provider Identifier (NPI) is 1205834819, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Klein's specialty?
- William Klein is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William Klein located?
- William Klein's practice location on file with NPPES is 1501 Superior Ave, Newport Beach, CA 92663-3600.
- What is William Klein's phone number?
- The practice phone number listed in the NPPES registry for William Klein is (949) 274-8030.
- Does William Klein accept Medicare?
- William Klein is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Klein's NPI active?
- Yes — William Klein's NPI (1205834819) is active in the NPPES registry as of the last update on 2008-01-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.