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Dr. William Seasly DDS

Dentist in Downers Grove, IL · enumerated 2010 · authorized official William Seasly, Owner.

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

National Provider Identifier

1942503594

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Registry record

Entity type Organization (Type 2)
Legal business name Dr. William Seasly DDS
Practice address 6311 Woodward Ave, Downers Grove, IL, 60516
Phone (630) 541-3119
Fax (630) 324-6361
Enumeration date Dec 20, 2010
Last updated in NPPES Dec 20, 2010

Taxonomy & classification

122300000X Dentist Dental Providers · License 019.027239 (IL) Primary

Authorized official

Name William Seasly
Title Owner
Phone (630) 541-3119

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 Dr. William Seasly DDS?
The NPI for Dr. William Seasly DDS is 1942503594, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Dr. William Seasly DDS?
NPPES lists William Seasly (Owner) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2010-12-20.