NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Grechen Holthausen

Clinical Social Worker in Guilford, CT · enumerated 2016 · practices at Town of Guilford.

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

National Provider Identifier

1174972780

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Grechen Holthausen
Sex Female
Practice address 36 Graves Ave, Guilford, CT, 06437
Phone (203) 453-8047
Fax (203) 453-8044
Enumeration date Jun 6, 2016
Last updated in NPPES Jun 6, 2016

Taxonomy & licenses

1041C0700X Clinical Social Worker Behavioral Health & Social Service Providers · License 2986 (CT) Primary

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 → Validate an NPI →

Frequently asked questions

What is the NPI number for Grechen Holthausen?
The National Provider Identifier (NPI) for Grechen Holthausen is 1174972780, a Type 1 (individual) record in the CMS NPPES registry.
Where does Grechen Holthausen practice?
The practice location on file with NPPES is in Guilford, CT. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-06-06.