Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Tess Gelderloos, MA, BCBA LBA

Behavior Analyst in Great Falls, MT · enumerated 2014 · practices at Big Sky Therapeutic Services, Pllc.

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

National Provider Identifier

1144626342

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)

Name Tess Gelderloos

Credential MA, BCBA LBA

Sex Female

Practice address 1601 2nd Ave N Ste 700, Great Falls, MT, 59401

Phone (406) 205-0452

Fax (406) 545-2276

Enumeration date Nov 15, 2014

Last updated in NPPES Feb 9, 2026

Taxonomy & licenses

103K00000X Behavior Analyst Behavioral Health & Social Service Providers · License 1-14-16072 (MT) 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.

Read the full guide → Validate an NPI →

Frequently asked questions

What is the NPI number for Tess Gelderloos?

The National Provider Identifier (NPI) for Tess Gelderloos is 1144626342, a Type 1 (individual) record in the CMS NPPES registry.

Where does Tess Gelderloos practice?

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

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-02-09.