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

Dr. Mark Oliver Day Sr., D.C., CSCS, DACBSP

Sports Physician Chiropractor in Maysville, KY · enumerated 2005.

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

National Provider Identifier

1952301152

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Registry record

Entity type Individual (Type 1)

Name Dr. Mark Oliver Day Sr.

Credential D.C., CSCS, DACBSP

Sex Male

Practice address Maysville, KY, 41056

Phone (606) 564-6831

Fax (606) 564-8300

Enumeration date Jul 28, 2005

Last updated in NPPES Jun 14, 2021

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

Taxonomy & licenses

111NS0005X Sports Physician Chiropractor Chiropractic Providers · License 1787 (OH) Secondary

111NS0005X Sports Physician Chiropractor Chiropractic Providers · License 249851 (KY) Primary

DC · Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC credential

Other identifiers

Identifier	Type	State	Issuer
311345271	Other	-	TAX ID OTHER INS. NUMBER
85001352	Medicaid	KY	-
0868717	Medicaid	OH	-
000000016455	Other	KY	ANTHEM PROVIDER NUMBER
000000016455	Other	OH	ANTHEM PROVIDER NUMBER

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 specialty is Mark Day?

Mark Day is registered in NPPES with the primary taxonomy of Sports Physician Chiropractor. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2021-06-14.