William Klein, MD
NPI 1659359578 · Internal Medicine Physician · Great Neck, NY
Enrolled with Medicare as Practitioner - General Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Klein, MD is a Internal Medicine Physician provider in Great Neck, NY (NPI 1659359578).
Provider details
- NPI number
- 1659359578
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 205508 (NY)
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
3,263 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 | 997 | $150 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 591 | $9 |
| 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 | 368 | $19 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report93000 | 235 | $17 |
| Injection of Drug Or Substance Under Skin Or Into Muscle96372 | 166 | $17 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent Visit |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 71 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Rosuvastatin Calcium | 210 | 65 |
| Atorvastatin Calcium | 171 | 41 |
| Amlodipine Besylate | 159 | 38 |
| Levothyroxine Sodium | 125 | 32 |
| Metoprolol Succinate | 110 | 29 |
| Zolpidem Tartrate | 86 | 19 |
| Escitalopram Oxalate |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,663 across 84 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
- 2006-01-03
- Last updated
- 2011-05-03
Frequently asked questions
- What is William Klein's NPI number?
- William Klein's National Provider Identifier (NPI) is 1659359578, 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 1000 Northern Blvd, Great Neck, NY 11021-5312.
- What is William Klein's phone number?
- The practice phone number listed in the NPPES registry for William Klein is (516) 627-4433.
- 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 (1659359578) is active in the NPPES registry as of the last update on 2011-05-03.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.