Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Clarrisa C. Hamann, APN-CNP

Nurse Practitioner in Highland Park, IL · enumerated 2007.

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

National Provider Identifier

1255542718

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Registry record

Entity type Individual (Type 1)

Name Clarrisa C. Hamann

Credential APN-CNP

Sex Female

Practice address 777 Park Ave. West, Highland Park, IL, 60035

Phone (847) 480-3956

Fax (847) 480-2861

Enumeration date May 25, 2007

Last updated in NPPES Jun 18, 2019

Taxonomy & licenses

163W00000X Registered Nurse Nursing Service Providers · License 041271088 (IL) Secondary

363L00000X Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 209-004281 (IL) 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

How do I verify Clarrisa Hamann's NPI record?

Cross-check NPI 1255542718 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Is NPI 1255542718 active?

Yes, as of the latest NPPES snapshot, NPI 1255542718 is active (record last updated 2019-06-18).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-06-18.