IndividualActive
Mark Collister, L.S.W.
NPI 1225078082 · Social Worker · Williamsport, PA
Mark Collister, L.S.W. is a Social Worker provider in Williamsport, PA (NPI 1225078082).
Provider details
- NPI number
- 1225078082
- Entity type
- Individual
- Primary specialty
- Social WorkerBehavioral Health & Social Service Providers
- Credential
- L.S.W.
- Sex
- Male
- License
- SW124379 (PA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
Detailed profile(91/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
435 W 4th St
Williamsport, PA 17701-6001
Phone: (570) 322-7873
Fax: (570) 322-8026
Street-level locationGet directions
Mailing address
10 Catherine Dr
Williamsport, PA 17701-1292
Registry dates
- Enumerated
- 2006-06-08
- Last updated
- 2007-07-08
Frequently asked questions
- What is Mark Collister's NPI number?
- Mark Collister's National Provider Identifier (NPI) is 1225078082, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Collister's specialty?
- Mark Collister is listed in the NPPES registry with a primary specialty of Social Worker (Behavioral Health & Social Service Providers).
- Where is Mark Collister located?
- Mark Collister's practice location on file with NPPES is 435 W 4th St, Williamsport, PA 17701-6001.
- What is Mark Collister's phone number?
- The practice phone number listed in the NPPES registry for Mark Collister is (570) 322-7873.
- Is Mark Collister's NPI active?
- Yes — Mark Collister's NPI (1225078082) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.