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David S Klein, MD

David S Klein is a Diagnostic Radiology Physician provider (Radiology) practicing in Norwalk, CT, registered in the NPPES registry with NPI 1427021021 since 2006. The credential MD stands for Doctor of Medicine.

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NPI 1427021021
Entity type Individual (Type 1)
Name David S Klein
Credential MD
Sex Male
Practice address 148 EAST AVE, Norwalk, CT, 06851
Phone 2038529913
Enumeration date 2006-02-13
Last updated in NPPES 2010-02-16

Taxonomy & licenses

Taxonomy code Specialty Primary License State
2085R0202X Diagnostic Radiology Physician Primary 039370 CT

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Copy-ready billing details
Provider: David Klein, MD
NPI: 1427021021
Taxonomy: 2085R0202X (Diagnostic Radiology Physician)
Address: 148 EAST AVE, Norwalk, CT, 06851

Other providers at this practice address

NPI Name Type Specialty Location
1992707616 Richard Stieglitz Individual Physical Therapist Norwalk, CT
1326032285 Andrew Parker Individual Otolaryngology Physician Norwalk, CT
1003897687 Heather Frimmer Individual Diagnostic Radiology Physician Norwalk, CT
1699756023 Steven Bernstein Individual Diagnostic Radiology Physician Norwalk, CT
1467436733 Agnieszka Matczuk Individual Allergy & Immunology Physician Norwalk, CT
1174596902 Avelino Maitem Individual Diagnostic Radiology Physician Norwalk, CT
1780657510 Pradip Pathare Individual Radiation Oncology Physician Norwalk, CT
1912970732 Alan Levine Individual Diagnostic Radiology Physician Norwalk, CT

Verify this record

Cross-check NPI 1427021021 against the authoritative CMS record: view David S Klein on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

Where does David Klein practice?
The practice location on file with NPPES is in Norwalk, CT. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for David Klein?
The National Provider Identifier (NPI) for David Klein is 1427021021, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2010-02-16.