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Mrs. Heather Mahoney O'Sullivan, NP

Gerontology Nurse Practitioner in Waltham, MA · enumerated 2007 · practices at Optum Palliative and Hospice Care, Inc..

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

National Provider Identifier

1700939907

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Registry record

Entity type Individual (Type 1)
Name Mrs. Heather Mahoney O'Sullivan
Credential NP
Sex Female
Practice address 950 Winter St, Suite 3800, Waltham, MA, 02451
Phone (781) 472-8491
Enumeration date Jan 19, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

363LG0600X Gerontology Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 211831 (MA) Primary
NP · Nurse Practitioner: An advanced practice registered nurse with graduate training, licensed to diagnose and treat, often with prescriptive authority. About the NP 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

Is NPI 1700939907 active?
Yes, as of the latest NPPES snapshot, NPI 1700939907 is active (record last updated 2007-07-08).
How do I verify Heather O'Sullivan's NPI record?
Cross-check NPI 1700939907 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.