Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mark L. Collister, L.S.W.

Social Worker in Williamsport, PA · enumerated 2006.

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

National Provider Identifier

1225078082

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Registry record

Entity type Individual (Type 1)

Name Mark L. Collister

Credential L.S.W.

Sex Male

Practice address 435 W 4th St, Williamsport, PA, 17701

Phone (570) 322-7873

Fax (570) 322-8026

Enumeration date Jun 8, 2006

Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

104100000X Social Worker Behavioral Health & Social Service Providers · License SW124379 (PA) Primary

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

How do I verify Mark Collister's NPI record?

Cross-check NPI 1225078082 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Is NPI 1225078082 active?

Yes, as of the latest NPPES snapshot, NPI 1225078082 is active (record last updated 2007-07-08).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.