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

Dr. John Whitney Mercer Jr., MD

Obstetrics & Gynecology Physician in Nampa, ID · enumerated 2007.

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

National Provider Identifier

1205988540

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Registry record

Entity type Individual (Type 1)
Name Dr. John Whitney Mercer Jr.
Credential MD
Sex Male
Practice address Nampa, ID, 83687
Phone (208) 302-1400
Fax (208) 302-1455
Enumeration date Jan 17, 2007
Last updated in NPPES Sep 2, 2025

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

Taxonomy & licenses

207V00000X Obstetrics & Gynecology Physician Allopathic & Osteopathic Physicians · License L023779 (LA) Secondary
207V00000X Obstetrics & Gynecology Physician Allopathic & Osteopathic Physicians · License CDR.0000210 (CO) Secondary
207V00000X Obstetrics & Gynecology Physician Allopathic & Osteopathic Physicians · License 3971468 (ID) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
L023779 Other LA STATE LICENSE
9000166884 Medicaid CO -
1487163 Medicaid LA -

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 John Mercer?
The National Provider Identifier (NPI) for John Mercer is 1205988540, a Type 1 (individual) record in the CMS NPPES registry.
Where does John Mercer practice?
The practice location on file with NPPES is in Nampa, ID. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-09-02.