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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Carol Ann Mertins, APRN, BC

Psychiatric/Mental Health Nurse Practitioner in Watertown, WI · enumerated 2008.

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

National Provider Identifier

1366606618

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Registry record

Entity type Individual (Type 1)
Name Dr. Carol Ann Mertins
Credential APRN, BC
Sex Female
Practice address Watertown, WI, 53094
Phone (920) 206-7797
Fax (920) 206-0870
Enumeration date Jul 16, 2008
Last updated in NPPES Apr 5, 2017

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

364SA2200X Adult Health Clinical Nurse Specialist Physician Assistants & Advanced Practice Nursing Providers · License 3055-33 (WI) Secondary
363LP0808X Psychiatric/Mental Health Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 3055-33 (WI) Primary
APRN · Advanced Practice Registered Nurse: An umbrella credential covering NPs, CRNAs, CNMs, and clinical nurse specialists. About the APRN credential

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

What is the NPI number for Carol Mertins?
The National Provider Identifier (NPI) for Carol Mertins is 1366606618, a Type 1 (individual) record in the CMS NPPES registry.
Where does Carol Mertins practice?
The practice location on file with NPPES is in Watertown, WI. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2017-04-05.