Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Douglas D. Tassi, O.D.

Optometrist in Sioux Falls, SD · enumerated 2005.

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

National Provider Identifier

1306840111

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Registry record

Entity type Individual (Type 1)

Name Dr. Douglas D. Tassi

Credential O.D.

Sex Male

Practice address 2501 W 22nd St, Sioux Falls, SD, 57105

Phone (605) 336-3230

Enumeration date Jun 9, 2005

Last updated in NPPES Sep 4, 2008

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 1655 (IA) Secondary

152W00000X Optometrist Eye and Vision Services Providers · License 649 (SD) Primary

152W00000X Optometrist Eye and Vision Services Providers · License T03000 (MO) Secondary

152W00000X Optometrist Eye and Vision Services Providers · License 1131 (NE) Secondary

OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

Other identifiers

Identifier	Type	State	Issuer
298638800	Medicaid	MN	-
5119065	Medicaid	IA	-
10025032100	Medicaid	NE	-
46044447400	Medicaid	NE	-
9200750	Medicaid	SD	-
9200754	Medicaid	SD	-
9200752	Medicaid	SD	-
9200753	Medicaid	SD	-
3119065	Medicaid	IA	-

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 Douglas Tassi practice?

The practice location on file with NPPES is in Sioux Falls, SD. Providers can have multiple locations; NPPES lists the primary practice address.

What is the NPI number for Douglas Tassi?

The National Provider Identifier (NPI) for Douglas Tassi is 1306840111, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-09-04.