Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Abigail D Duffy, MS CCC-SLP

Speech-Language Pathologist in Crystal Lake, IL · enumerated 2022.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1407571995

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Registry record

Entity type Individual (Type 1)

Name Abigail D Duffy

Credential MS CCC-SLP

Sex Female

Practice address 394 Federal Dr, Crystal Lake, IL, 60014

Phone (815) 459-3810

Enumeration date Oct 6, 2022

Last updated in NPPES Oct 6, 2022

Taxonomy & licenses

235Z00000X Speech-Language Pathologist Speech, Language and Hearing Service Providers · License 235Z00000X (IL) Secondary

235Z00000X Speech-Language Pathologist Speech, Language and Hearing Service Providers · License 146016660 (IL) Primary

Other identifiers

Identifier	Type	State	Issuer
60014	Other	IL	COMMERCIAL

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 Abigail Duffy?

Abigail Duffy is registered in NPPES with the primary taxonomy of Speech-Language Pathologist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2022-10-06.