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

Diane Mcmillan, MS, UNDER LMFT SUPER

Marriage & Family Therapist in Ada, OK · enumerated 2011 · practices at Chickasaw Nation.

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

National Provider Identifier

1538468921

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Registry record

Entity type Individual (Type 1)
Name Diane Mcmillan
Credential MS, UNDER LMFT SUPER
Sex Female
Practice address Ada, OK, 74820
Phone (580) 436-1222
Enumeration date Mar 24, 2011
Last updated in NPPES Mar 24, 2011

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

Taxonomy & licenses

106H00000X Marriage & Family Therapist Behavioral Health & Social Service Providers 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.

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Frequently asked questions

Where does Diane Mcmillan practice?
The practice location on file with NPPES is in Ada, OK. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Diane Mcmillan?
The National Provider Identifier (NPI) for Diane Mcmillan is 1538468921, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-03-24.