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

Gregory Alan Oltmann, D.C.

Chiropractor in Tigard, OR · enumerated 2013 · practices at Gregory Oltmann Dc LLC.

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

National Provider Identifier

1588907570

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Registry record

Entity type Individual (Type 1)
Name Gregory Alan Oltmann
Credential D.C.
Sex Male
Practice address Tigard, OR, 97223
Phone (503) 716-8281
Fax (037) 168-7835
Enumeration date Mar 28, 2013
Last updated in NPPES Jun 7, 2022

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

Taxonomy & licenses

111N00000X Chiropractor Chiropractic Providers · License 5138 (OR) Primary
DC · Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC 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 Gregory Oltmann?
The National Provider Identifier (NPI) for Gregory Oltmann is 1588907570, a Type 1 (individual) record in the CMS NPPES registry.
Where does Gregory Oltmann practice?
The practice location on file with NPPES is in Tigard, OR. 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 2022-06-07.