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MS. CECILIA CASSIDY LENAHAN LCPC, LAC
NPI 1659767580
Counselor - Addiction (Substance Use Disorder) in Great Falls, MT

Active since April 07, 2015PECOS EnrolledAccepts Medicare Assignment
510 1ST AVE N, GREAT FALLS, MT 59401(406) 454-6973(406) 791-9277 Get Directions Write a Review

NPPES record last updated: April 13, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Apr 13, 2026, May 10, 2024, Oct 30, 2023 and 1 more (4 updates tracked since 2023).

About Ms. Cecilia Cassidy Lenahan Lcpc, Lac NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MS. CECILIA CASSIDY LENAHAN LCPC, LAC (NPI 1659767580) is an individual addiction (substance use disorder) provider in Great Falls, Montana, licensed in Montana (BBH-LAC-LIC-4258) and active in the NPI registry since April 2015. She is enrolled in Medicare PECOS, maintains 2 additional practice locations, and is a graduate of Other (2007).

NPPES Registry Identity

NPI1659767580
Entity TypeIndividualFemale
Primary Taxonomy101YA0400X
Provider Legal NameMS. CECILIA CASSIDY LENAHANCredential: LCPC, LAC
Location Address510 1ST AVE NGreat Falls, MT 59401-2592
Mailing Address601 1st Ave NGreat Falls, MT 59401-2510 · (406) 454-6973 · Fax (406) 791-9277
Phone(406) 454-6973
Fax(406) 791-9277
Sole ProprietorNo
Medical School CMSOtherGraduated 2007
Enumeration DateApril 7, 2015
Last NPPES UpdateApril 13, 20264 updates tracked since enumeration
NPPES CertifiedApril 13, 2026
✔ NPI 1659767580 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyCounselor · Addiction (Substance Use Disorder)Behavioral Health & Social Service Providers
Taxonomy Code101YA0400X
License✔ Licensed in MT · BBH-LAC-LIC-4258
Also ListedCounselor · ProfessionalTaxonomy 101YP2500X · License BBH-LCPC-LIC-81696 (MT)
510 1ST AVE N, Great Falls, MT 59401
Open in Google Maps ↗

Secondary Practice Locations 2

Location 13911 Central AveGreat Falls, MT 59405-1637 · Phone (406) 454-6973 · Fax (406) 791-9277
Location 22400 Central Ave Rm 118Great Falls, MT 59401-3915 · Phone (406) 454-6973 · Fax (406) 791-9277

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Montana, Mountain Health CO-OP.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Ms. Cecilia Cassidy Lenahan Lcpc, Lac is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID345730081
PECOS Enrollment IDI20251110003227
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment– Home Health Agency– Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Other Providers at the Same Location NPPES 5

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

ELIJAH LOGAN SUNDSTROM ACLC
Counselor (Addiction (Substance Use Disorder))
510 1ST AVE N
GREAT FALLS, MT 59401
Cascade County (406) 454-6973
MRS. JULIE TROSPER LCPC, ACLC
Counselor (Mental Health)
510 1ST AVE N
GREAT FALLS, MT 59401
Cascade County (406) 454-6973
MANDY KNIGHT LCSW
Social Worker (Clinical)
510 1ST AVE N
GREAT FALLS, MT 59401
Cascade County (406) 454-6973
SHANNON M HINES LMSW, CSWE
Social Worker (Clinical)
510 1ST AVE N
GREAT FALLS, MT 59401
Cascade County (406) 454-6973
JOSEPH EDWARD HANSEN LCSW
Social Worker (Clinical)
510 1ST AVE N
GREAT FALLS, MT 59401
Cascade County (406) 454-6973

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Cecilia Lenahan's NPI number?

The NPI number for Cecilia Lenahan is 1659767580. It was assigned to this individual provider in the NPPES registry on April 7, 2015.

Where is Cecilia Lenahan located?

Cecilia Lenahan practices at 510 1st Ave N, Great Falls, MT 59401. The listed phone number is (406) 454-6973.

What is Cecilia Lenahan's specialty?

The primary specialty registered for this NPI is Counselor, specializing in Addiction (Substance Use Disorder), with taxonomy code 101YA0400X.

Is Cecilia Lenahan enrolled in Medicare?

Yes. Cecilia Lenahan is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Cecilia Lenahan accept?

Health plans from Blue Cross and Blue Shield of Montana and Mountain Health CO-OP list Cecilia Lenahan as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Cecilia Lenahan was last updated on April 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.