Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. William Americo Longo, M.D.

Surgery Physician in Middletown, CT · enumerated 2006.

Data current as of Jul 11, 2026 · sourced from CMS NPPES

National Provider Identifier

1861471179

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Registry record

Entity type Individual (Type 1)

Name Dr. William Americo Longo

Credential M.D.

Sex Male

Practice address 520 Saybrook Rd, Middletown, CT, 06457

Phone (860) 346-2608

Fax (860) 347-4691

Enumeration date Jan 13, 2006

Last updated in NPPES Jul 28, 2010

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 023666 (CT) Primary

2086S0129X Vascular Surgery Physician Allopathic & Osteopathic Physicians · License 023666 (CT) Secondary

2086X0206X Surgical Oncology Physician Allopathic & Osteopathic Physicians · License 023666 (CT) Secondary

208C00000X Colon & Rectal Surgery Physician Allopathic & Osteopathic Physicians · License 023666 (CT) Secondary

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

Other identifiers

Identifier	Type	State	Issuer
001236660	Medicaid	CT	—

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.

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Frequently asked questions

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

What specialty is William Longo?

William Longo is registered in NPPES with the primary taxonomy of Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2010-07-28.