WILLIAM M KLEIN MD
NPI 1659359578
Internal Medicine in New Hyde Park, NY

Q: What is William Klein's NPI number?

The NPI number for William Klein is 1659359578. It was assigned to this individual provider in the NPPES registry on January 3, 2006.

Q: What is William Klein's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for William Klein was last updated on August 6, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since January 03, 2006PECOS EnrolledAccepts Medicare Assignment

1 HOLLOW LN STE 109, NEW HYDE PARK, NY 11042(516) 627-4433(516) 627-0552 Get Directions Write a Review

NPPES record last updated: August 6, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

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About William M Klein Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WILLIAM M KLEIN MD (NPI 1659359578) is an individual internal medicine provider in New Hyde Park, New York, licensed in New York (205508) and active in the NPI registry since January 2006. He is enrolled in Medicare PECOS, is affiliated with North Shore University Hospital, and maintains a secondary practice location in Great Neck.

NPPES Registry Identity

NPI1659359578

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameWILLIAM M KLEINCredential: MD

Location Address1 HOLLOW LN STE 109New Hyde Park, NY 11042-1215

Mailing Address1 Hollow Ln Ste 109New Hyde Park, NY 11042-1215 · (516) 627-4433 · Fax (516) 627-0552

Phone(516) 627-4433

Fax(516) 627-0552

Sole ProprietorNo

Medical School CMSIcahn School Of Medicine At Mount SinaiGraduated 1994

Enumeration DateJanuary 3, 2006

Last NPPES UpdateAugust 6, 2026

NPPES CertifiedAugust 6, 2026

✔ NPI 1659359578 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in NY · 205508

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

1 HOLLOW LN STE 109, New Hyde Park, NY 11042

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Secondary Practice Location 1

Location 11000 Northern Blvd Ste 230Great Neck, NY 11021-5341 · Phone (516) 627-4433 · Fax (516) 627-0552

Other Identifiers 8

Other136958Vytra

Other3651757Cigna

OtherA289291199

OtherWK07R53510NY · Blue Shield

OtherP3695174Oxford

Other205508Hip

Other4C4799Healthnet

Other2594094Ghi

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

William M Klein Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID8123050564

PECOS Enrollment IDI20050907000059

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show William Klein reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

North Shore Primary Care Medical Associates, PC

Same address

Internal Medicine

1 HOLLOW LN STE 109
New Hyde Park, NY 11042

Reassigned Medicare billing, New York enrollment
8 clinicians in this Medicare group

NPI 1548287410 (516) 627-4433

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 22

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

997 services189 patients

Insertion of needle into vein for collection of blood sample 36415

This procedure involves inserting a small needle into a vein, typically in your arm, to collect a blood sample. It's a quick and simple process to help diagnose or monitor health conditions. You may feel a small prick, but discomfort is minimal.

591 services187 patients

Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000

An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.

235 services178 patients

Injection of drug or substance under skin or into muscle 96372

This procedure involves administering medication directly under the skin or into a muscle. A small needle is used to inject the drug, allowing it to be absorbed quickly into the bloodstream. It's a common method for delivering a variety of medications.

166 services40 patients

Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit G0439

An annual wellness visit is a yearly appointment with your primary care provider to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's a subsequent visit, meaning it follows an initial assessment.

138 services138 patients

Detection test by immunoassay with direct visual observation for severe acute respiratory syndrome coronavirus 2 (covid-19) 87811

This is a test to detect COVID-19, the virus causing severe respiratory illness. It uses a method called immunoassay, which identifies the virus by its unique proteins. The test is directly observed for accuracy. It helps determine if you're currently infected.

127 services78 patients

Annual depression screening, 5 to 15 minutes G0444

An annual depression screening is a short, routine evaluation to check for signs of depression. It involves answering a series of questions about your feelings, thoughts, and behaviors. The process takes about 15 minutes and helps detect depression early for better management.

126 services126 patients

Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg J3420

This is a procedure where a small dose of Vitamin B-12, also known as Cyanocobalamin, is injected into your body. This vitamin is essential for nerve function and the production of red blood cells. It's often used to treat vitamin B-12 deficiency.

117 services23 patients

Administration of influenza virus vaccine G0008

The administration of the influenza virus vaccine, also known as the flu shot, is a simple procedure to protect against the flu. A healthcare provider injects a small dose of the vaccine into your arm. This stimulates your immune system to produce antibodies, which will help your body fight off the flu if exposed.

113 services112 patients

Influenza vaccine split virus, preservative free 90662

The Influenza Vaccine Split Virus, preservative-free, is a flu shot to protect against the influenza virus. It is made from parts of inactivated flu viruses and doesn't contain preservatives, reducing potential side effects. It helps your body develop immunity to the flu.

108 services107 patients

Urinalysis, manual test 81002

A urinalysis is a simple, non-invasive test that checks the urine for various elements such as sugar, protein, and signs of infection. It can help detect many common conditions, including kidney disease and diabetes. The manual test involves a lab technician examining a urine sample.

90 services77 patients

Office or other outpatient visit for the evaluation and management of established patient that may not require presence of healthcare professional 99211

This service involves an outpatient visit for established patients who may not need direct interaction with a healthcare professional. It could include reviewing test results, monitoring existing conditions, or adjusting treatment plans. It's typically done remotely, ensuring your comfort and convenience.

75 services11 patients

Detection test by immunoassay with direct visual observation for influenza virus 87804

This is a test that identifies the influenza virus in your body. It works by using an immunoassay, a method that detects the presence of the virus through an immune response. The results are directly observable, making it a quick and efficient way to diagnose flu.

70 services53 patients

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

46 services40 patients

Chronic care management services, first 20 minutes of clinical staff time directed by health care professional, per calendar month 99490

Chronic care management services involve a healthcare professional directing clinical staff in managing your chronic conditions. This includes the first 20 minutes per month of services like medication management, care coordination, and health monitoring to help improve your health and quality of life.

26 services14 patients

Detection test by immunoassay with direct visual observation for respiratory syncytial virus 87807

This is a test to identify the respiratory syncytial virus, a common cause of lung and respiratory tract infections. It uses immunoassay, a method that detects the virus through a reaction between the virus and specific antibodies. The result is visually observed.

19 services19 patients

Test to measure rate of airflow 94375

This test, known as spirometry, measures how much air you can breathe in and out, and how quickly you can do so. It helps assess your lung function and can be used to diagnose or monitor conditions like asthma or COPD.

18 services13 patients

Detection test by immunoassay with direct visual observation for streptococcus, group a (strep) 87880

A detection test by immunoassay for Group A Strep is a quick procedure to identify a bacterial infection in your throat. It involves taking a throat swab and applying it to a test strip, which changes color if Strep bacteria are present.

15 services12 patients

Administration of vaccine 90471

Administering a vaccine involves injecting a small, safe piece of a virus or bacteria into your body. This triggers your immune system to recognize and fight off the disease in the future. It's a vital tool in preventing serious illnesses and maintaining public health.

15 services15 patients

Annual wellness visit; includes a personalized prevention plan of service (pps), initial visit G0438

An annual wellness visit is a yearly appointment with your doctor to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's an opportunity to discuss your health status and goals and get a plan tailored for you.

15 services15 patients

Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306

This is a heart ultrasound, also known as an echocardiogram. It uses sound waves to create pictures of your heart, showing how blood flows through it. The color depicts the blood flow's speed and direction. It also checks the heart's valves to ensure they're working properly.

13 services13 patients

Pneumococcal conjugate vaccine, 20 valent (pcv20), for intramuscular use 90677

The Pneumococcal Conjugate Vaccine (PCV20) is a shot given to protect against 20 types of bacteria that can cause serious infections like pneumonia and meningitis. It's administered through a muscle, usually in the arm. It's important for overall health.

11 services11 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

North Shore University Hospital

Acute Care Hospitals · Manhasset, NY

4/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number330106

Location300 Community DriveManhasset, NY 11030 · Nassau County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 11042 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$154.28 typical visit price

range $67.40 – $203.53

Typical copayment $38.57 (range $16.85 – $50.88)

Most-billed visit code 99204

Established Patient

$117.62 typical visit price

range $21.66 – $164.45

Typical copayment $29.40 (range $5.41 – $41.11)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

Reported Quality Measures

e-Prescribing

At least one permissible prescription written by the MIPS eligible clinician is queried for a drug formulary and transmitted electronically using certified EHR technology.

100%1,923 patients5/55-star benchmark: 100%

Health Information Exchange

The MIPS eligible clinician that transitions or refers their patient to another setting of care or health care clinician (1) uses CEHRT to create a summary of care record; and (2) electronically transmits such summary to a receiving health care clinician for…

25%550 patients2/55-star benchmark: 96%

Medication Reconciliation

The MIPS eligible clinician performs medication reconciliation for at least one transition of care in which the patient is transitioned into the care of the MIPS eligible clinician.

100%398 patients5/55-star benchmark: 100%

Patient-Specific Education

The MIPS eligible clinician must use clinically relevant information from CEHRT to identify patient-specific educational resources and provide access to those materials to at least one unique patient seen by the MIPS eligible clinician.

89%558 patients4/55-star benchmark: 99%

Provide Patient Access

At least one patient seen by the MIPS eligible clinician during the performance period is provided timely access to view online, download, and transmit to a third party their health information subject to the MIPS eligible clinician's discretion to withhold…

93%558 patients4/55-star benchmark: 100%

Secure Messaging

For at least one unique patient seen by the MIPS eligible clinician during the performance period, a secure message was sent using the electronic messaging function of CEHRT to the patient (or the patient-authorized representative), or in response to a secure…

1%558 patients1/55-star benchmark: 59%

Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390

DME-Oxygen and Supplies · category DC002N

2 suppliers20 claims20 services$67.95 avg. paid by Medicare

Supply allowance for therapeutic continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service K0553

DME-Other DME · category DE017N

3 suppliers14 claims14 services$213.11 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 4

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

NORTH SHORE PRIMARY CARE MEDICAL ASSOCIATES, PC

Internal Medicine

1 HOLLOW LN STE 109
NEW HYDE PARK, NY 11042

Nassau County (516) 627-4433

DAVID G EDELSON MD

Internal Medicine

1 HOLLOW LN STE 109
NEW HYDE PARK, NY 11042

Nassau County (516) 627-4433

DR. HILLARY KLEIN BEBERMAN D.O.

Family Medicine

1 HOLLOW LN STE 109
NEW HYDE PARK, NY 11042

Nassau County (516) 627-0552

HEALTH BRIDGE CONCIERGE MEDICINE

Internal Medicine

1 HOLLOW LN STE 109
NEW HYDE PARK, NY 11042

Nassau County (516) 627-4433

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Klein's NPI number?

The NPI number for William Klein is 1659359578. It was assigned to this individual provider in the NPPES registry on January 3, 2006.

Where is William Klein located?

William Klein practices at 1 Hollow Ln Ste 109, New Hyde Park, NY 11042. The listed phone number is (516) 627-4433.

What is William Klein's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is William Klein enrolled in Medicare?

Yes. William Klein is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for William Klein's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Klein reassigns Medicare benefits to North Shore Primary Care Medical Associates, PC (New Hyde Park, NY). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Klein's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is William Klein affiliated with any hospitals?

According to CMS data, William Klein is affiliated with North Shore University Hospital.

When was this NPI record last updated?

The NPPES record for William Klein was last updated on August 6, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.